Post by: The Golden Girl =D on April 24, 2010, 09:02:10 am
plz answer me as soon as u possible !
ohhhh and everyone who has doubts, post urs here too ;)
thx in advance
Post by: The Golden Girl =D on April 24, 2010, 09:34:45 am
Post by: nid404 on April 24, 2010, 09:38:44 am
Post by: The Golden Girl =D on April 24, 2010, 09:40:13 am
15min
k ....i'll wait .thx By the way
Post by: nid404 on April 24, 2010, 10:08:49 am
while reflecting, the points have to be equidistant on either sides of the mirror line(y=x) The dotted lines on my diagram will help
Traingle T has point ABC and the reflected T| has points A|B|C| repectively
ask again if you need help
Post by: The Golden Girl =D on April 24, 2010, 08:29:33 pm
thx in advance
Post by: astarmathsandphysics on April 24, 2010, 09:31:44 pm
Post by: astarmathsandphysics on April 24, 2010, 10:48:20 pm
Post by: The Golden Girl =D on April 25, 2010, 02:22:09 pm
sir, could u plz show me how to apply the rule i mentioned prior
thx in advance
Post by: Ghost Of Highbury on April 25, 2010, 02:25:16 pm
also, what rule are u talking about ? do u mean the (c) (ii) part??
Post by: The Golden Girl =D on April 25, 2010, 02:32:10 pm
Do u want me to do the (e) part?
also, what rule are u talking about ? do u mean the (c) (ii) part??
ya sure ........ um no this rule "transformation matrix * object = image" ......
thx By the way :)
Post by: Ghost Of Highbury on April 25, 2010, 02:38:39 pm
the formula i used = Object matrix * Transformation matrix = Image Matrix
The object matrix can contain 3 sets of values as the object is a triangle, however , as it is difficult to work with a 3*3 matrix, we'll go for only two sets of values from the triangle. TAke any two sets of vertices
I chose : A : (8,6)
B : (6,10)
Now the image matrix will be A| : (6,8)
B| : (10,6)
Arrange this in a form of matrix (formula), note : the set of values is arranged vertically (column wise)
(8 6) * Transformation Matrix = (6 10)
(6 10) (8 6)
Now by simple algebra we'll get --> Transformation Matrix = (6 10) * (8 6 )-1
(8 6) (6 10)
The inverse of (8 6 ) is (10/44 -6/44)
(6 10) (-6/44 8/44)
Therefore Transformation Matrix = (6 10) * (10/44 -6/44) = (0 1)
(8 6) (-6/44 8/44) (1 0)
Thus the Transformation Matrix = (0 1)
(1 0)
----------------------------------------
nest up, e part
Post by: Ghost Of Highbury on April 25, 2010, 02:57:55 pm
Post by: Ghost Of Highbury on April 25, 2010, 03:01:47 pm
[EDIT] - Ok sent.
Post by: The Golden Girl =D on April 27, 2010, 11:19:40 am
Post by: rahuldevnani93 on April 28, 2010, 08:22:16 pm
i needed the formulas used to find the nth term.
Thanx a lot guys.
if ny files?
Email it to me at thunder.rahul@hotmail.com
Post by: Saladin on April 28, 2010, 08:41:05 pm
If you have any particular questions, please post them here.
And please do not give your e-mails.
Post by: haris94 on April 28, 2010, 09:00:02 pm
Post by: The Golden Girl =D on May 01, 2010, 07:07:18 am
thx in advance
Post by: Saladin on May 01, 2010, 07:19:15 am
Post by: Ghost Of Highbury on May 01, 2010, 09:27:37 am
As EF and DC are parallel, ED is the transverse and thus angle EDC is 71 degree.(180-109) (Corresponding angle to DEF)
As ED and BC are parallel , DC is the transverse and thus angle DCB is 109 (180-71) (Corresponding angles rule)
Now, as the polygon has 6 sides, the sum of the angles is (6-2) * 180 = 720 degrees.
They've mentioned that Angle FAB and ABC are equal thus, 720 - 95 - 109 - 71 - 109 = 336 degrees.
336 degrees is the sum of the equal angles FAB and ABC. Therefore , angle FAB = ABC = 336/2 = 168 degrees.
Post by: The Golden Girl =D on May 01, 2010, 12:18:05 pm
IGSCE Math Paper 2 Nov 02, Answer 12)b.
As EF and DC are parallel, ED is the transverse and thus angle EDC is 71 degree.(180-109) (Corresponding angle to DEF)
As ED and BC are parallel , DC is the transverse and thus angle DCB is 109 (180-71) (Corresponding angles rule)
Now, as the polygon has 6 sides, the sum of the angles is (6-2) * 180 = 720 degrees.
They've mentioned that Angle FAB and ABC are equal thus, 720 - 95 - 109 - 71 - 109 = 336 degrees.
336 degrees is the sum of the equal angles FAB and ABC. Therefore , angle FAB = ABC = 336/2 = 168 degrees.
thx again :)
Post by: Ghost Of Highbury on May 01, 2010, 12:36:48 pm
Post by: holtadit on May 01, 2010, 02:54:24 pm
0 1
For this matrice isnt the inverse:
0 1.5
But the MS says
0 1.5
Post by: astarmathsandphysics on May 01, 2010, 11:03:54 pm
Post by: Baladya on May 03, 2010, 01:53:37 pm
I was solving a question and the latest thing i could get to was: 21^2 = (2x)^2 + x^2 – (2)(2x)(x)(cos120). This is right in the mark scheme. Then what i do is : 441= 3x^2 +2x^2.(because i did cosine 120 times the answer of – (2)(2x)(x) which is -4x^2. And cosine 120 is -0.5... so (-0.5) (-4x^2)= 2x^2) And so its supposed to be 441=3x^2 + 2x^2.
However the asnwer in the mark scheme is 441= 7x^2.
From where the hell did the 7 come from?? plz help
(Answer of mark scheme: M1 212 = (2x)2 + x2 – 2.2x.x.cos120 oe
M1 441 = 7x2 )
Post by: The Golden Girl =D on May 03, 2010, 05:12:05 pm
Hey guys, i have this really annoying question that i m totally clueless with...
I was solving a question and the latest thing i could get to was: 21^2 = (2x)^2 + x^2 – (2)(2x)(x)(cos120). This is right in the mark scheme. Then what i do is : 441= 3x^2 +2x^2.(because i did cosine 120 times the answer of – (2)(2x)(x) which is -4x^2. And cosine 120 is -0.5... so (-0.5) (-4x^2)= 2x^2) And so its supposed to be 441=3x^2 + 2x^2.
However the asnwer in the mark scheme is 441= 7x^2.
From where the hell did the 7 come from?? plz help
(Answer of mark scheme: M1 212 = (2x)2 + x2 – 2.2x.x.cos120 oe
M1 441 = 7x2 )
i am confused , u gotta tell which question it is and where can i find it , so thati can answer
thx
Post by: Ghost Of Highbury on May 04, 2010, 07:03:01 am
Hey guys, i have this really annoying question that i m totally clueless with...
I was solving a question and the latest thing i could get to was: 21^2 = (2x)^2 + x^2 – (2)(2x)(x)(cos120). This is right in the mark scheme. Then what i do is : 441= 3x^2 +2x^2.(because i did cosine 120 times the answer of – (2)(2x)(x) which is -4x^2. And cosine 120 is -0.5... so (-0.5) (-4x^2)= 2x^2) And so its supposed to be 441=3x^2 + 2x^2.
However the asnwer in the mark scheme is 441= 7x^2.
From where the hell did the 7 come from?? plz help
(Answer of mark scheme: M1 212 = (2x)2 + x2 – 2.2x.x.cos120 oe
M1 441 = 7x2 )
The bold part is correct.
This is what you got incorrect - "21^2 = (2x)^2 + x^2 – (2)(2x)(x)(cos120)."
If you solve the red part u get, (2x)^2 + x^2 = 4x^2 + x^2 = 5x^2. (Notice : it is (2x) the whole squared not 2x^2)
If u carry on, :- 5x^2 + 2x^2 = 7x^2.
Silly mistake, happens. No problem.
Post by: Vin on May 04, 2010, 07:21:15 am
i use a Texas TI-30XB .. :) :)
Post by: Ghost Of Highbury on May 04, 2010, 07:39:02 am
Post by: Saladin on May 04, 2010, 07:45:49 am
We used. Fx - 991 Ms.
That calcualator is not allowed in an IGCSE Examination, I have no idea how they allowed you to use it.
Post by: Vin on May 04, 2010, 08:15:59 am
Post by: Saladin on May 04, 2010, 08:22:43 am
Please ask CIE here (http://ask.cie.org.uk/system/selfservice.controller?CONFIGURATION=1035&PARTITION_ID=1&TIMEZONE_OFFSET=&USERTYPE=1&CMD=ESCALATION_REQUEST)
Post by: Ghost Of Highbury on May 04, 2010, 08:51:02 am
That calcualator is not allowed in an IGCSE Examination, I have no idea how they allowed you to use it.
A guy used Fx-991 ES too. IN our school.
Post by: haris94 on May 04, 2010, 09:30:01 am
this is written on the first page of every paper
MATHEMATICS 0580/21, 0581/21
Paper 2 (Extended) May/June 2009
1 hour 30 minutes
Candidates answer on the Question Paper.
Additional Materials: Electronic calculator Geometrical instruments
Mathematical tables (optional) Tracing paper (optional)
Post by: Baladya on May 04, 2010, 09:56:56 am
The bold part is correct.
This is what you got incorrect - "21^2 = (2x)^2 + x^2 – (2)(2x)(x)(cos120)."
If you solve the red part u get, (2x)^2 + x^2 = 4x^2 + x^2 = 5x^2. (Notice : it is (2x) the whole squared not 2x^2)
If u carry on, :- 5x^2 + 2x^2 = 7x^2.
Silly mistake, happens. No problem.
omg.... I dunno what will i do in the IGCSE if i do these mistakes :S
Anyway thx man :D
By the way about the calculators, The best are fx-570 ES(which i use) and 991 ES. They are so amazing u can do anything especially i love that u can put fractions :D xD
Quicki for dummies :D: Make n the subject in y=m^2-4n^2, Why can't i just do this: minus m^2 from both sides so it will go to the left. It will be like this y-m^2=-4n^2. Then divide by -4 both sides and square root. What is wrong in my method?? The right answer is n= SQUARE ROOT of m^2-y/4
Now a long one :P: http://www.freeexampapers.us/IGCSE/Maths/CIE/2008%20Jun/0580_s08_qp_4.pdf (http://www.freeexampapers.us/IGCSE/Maths/CIE/2008%20Jun/0580_s08_qp_4.pdf)
http://www.freeexampapers.us/IGCSE/Maths/CIE/2008%20Jun/0580_s08_ms_4.pdf (http://www.freeexampapers.us/IGCSE/Maths/CIE/2008%20Jun/0580_s08_ms_4.pdf)
Question Number 7. As the Mark scheme says, this is a cyclic quadrilateral. Is there any new rules about this?? Or is it normal and m just missing smth. Plz answer the questions too.
I know m asking a lot but plz help cuz only a week for exam and somewhy i m confused tho i get A* always :S :(
Post by: Vin on May 04, 2010, 10:33:54 am
the thing there are specific rules abt which calci u use..
commin to calcis of casio...ny model abv fx-100 ms is NOT ALLOWED !!
thts wat i wantd 2 clear..!! :)
Post by: Vin on May 04, 2010, 10:50:46 am
y= m^2 - 4 n^2
y + 4 n^2 = m^2
4 n^2 = m^2 - y
n^2 = m^2 - y (whole)/4
n = root m2 - y (whole) /4
Post by: Ghost Of Highbury on May 04, 2010, 10:52:07 am
omg.... I dunno what will i do in the IGCSE if i do these mistakes :S
Anyway thx man :D
By the way about the calculators, The best are fx-570 ES(which i use) and 991 ES. They are so amazing u can do anything especially i love that u can put fractions :D xD
Quicki for dummies :D: Make n the subject in y=m^2-4n^2, Why can't i just do this: minus m^2 from both sides so it will go to the left. It will be like this y-m^2=-4n^2. Then divide by -4 both sides and square root. What is wrong in my method?? The right answer is n= SQUARE ROOT of m^2-y/4
Now a long one :P: http://www.freeexampapers.us/IGCSE/Maths/CIE/2008%20Jun/0580_s08_qp_4.pdf (http://www.freeexampapers.us/IGCSE/Maths/CIE/2008%20Jun/0580_s08_qp_4.pdf)
http://www.freeexampapers.us/IGCSE/Maths/CIE/2008%20Jun/0580_s08_ms_4.pdf (http://www.freeexampapers.us/IGCSE/Maths/CIE/2008%20Jun/0580_s08_ms_4.pdf)
Question Number 7. As the Mark scheme says, this is a cyclic quadrilateral. Is there any new rules about this?? Or is it normal and m just missing smth. Plz answer the questions too.
I know m asking a lot but plz help cuz only a week for exam and somewhy i m confused tho i get A* always :S :(
Ok thats the right method..
still ill solve it for ya.
y = m2 - 4n2
y - m2 = -4n2
Dividing both by -4
therefore
n =
long q, next up
Post by: Ghost Of Highbury on May 04, 2010, 10:57:08 am
Post by: Ghost Of Highbury on May 04, 2010, 11:04:50 am
y = 25 degree (OAB is isosceles therefore 180-130 = 50. 50/2 = 25)
z = 180-25 -40 = 180-65 = 115 degree.
iii) OCT = 90 degree, as OC is the radius and it forms a right angle with a tangent.
iii) 210 degree. 130+90.
Post by: haris94 on May 04, 2010, 11:06:54 am
whoaaaa @ haris94 comon every person in the world noes tht igcse allows calci !!
the thing there are specific rules abt which calci u use..
commin to calcis of casio...ny model abv fx-100 ms is NOT ALLOWED !!
thts wat i wantd 2 clear..!! :)
i see what u mean
well i use fx-991ms and almost every1 in my class uses above fx-100ms
it has to be allowed or we would hv been notified
calculator covers arent allowed though
Post by: Vin on May 04, 2010, 11:14:08 am
Y = 25 OB n OA are radius
Z = 115… cyclic quad property..sum of angles are supplementary
OCT = 80 OC n OB radius so x = OCT
AOC = 230
Post by: Vin on May 04, 2010, 11:15:38 am
X = 40… alternate angles
Y = 25 OB n OA are radius
Z = 115… cyclic quad property..sum of angles are supplementary
OCT = 80 OC n OB radius so x = OCT
AOC = 230
oh im sorry i didnt see u already slvd A@di..
:)
Post by: The Golden Girl =D on May 04, 2010, 11:27:59 am
whoaaaa @ haris94 comon every person in the world noes tht igcse allows calci !!
the thing there are specific rules abt which calci u use..
commin to calcis of casio...ny model abv fx-100 ms is NOT ALLOWED !!
thts wat i wantd 2 clear..!! :)
wth?!!??!!? r u serious ?!!?!? i bought this calulator cuz my dad and my tutor who's an experienced teacher in teachin IG students told me it's allowed!?!? ....i am soo gonna die if what u're sayin is true "cuz it was really expensive :-["
Post by: holtadit on May 04, 2010, 11:31:17 am
wth?!!??!!? r u serious ?!!?!? i bought this calulator cuz my dad and my tutor who's an experienced teacher in teachin IG students told me it's allowed!?!? ....i am soo gonna die if what u're sayin is true "cuz it was really expensive :-["
Just dont make a fuss about it, most centres dont even know what calcs to allow in. Go in and do the exam - end of story.
The more drama we make about this issue the more likely it will be highlighted by CIE and then all centres will be informed. Just take your 991 MS into the exam and use it.
Post by: The Golden Girl =D on May 04, 2010, 11:33:12 am
thx in advance
Post by: Ghost Of Highbury on May 04, 2010, 11:34:02 am
Just dont make a fuss about it, most centres dont even know what calcs to allow in. Go in and do the exam - end of story.
The more drama we make about this issue the more likely it will be highlighted by CIE and then all centres will be informed. Just take your 991 MS into the exam and use it.
well said m8,
@golden gal - my friend took 991 ES imside and guess what? no problem! Chill, good luck :)
Post by: Ghost Of Highbury on May 04, 2010, 11:42:44 am
a) speed = distance / time
distance = 120-72 = 48.
time = 0830 - 0800 = 30 minutes = 0.5 hour
therefore speed = 48/0.5 = 96km/h
b) At 0900 hours, the distance covered is 0 because it is not moving (the line is constant at 40). Time = 1 hour. 0/1 = 0
Post by: The Golden Girl =D on May 04, 2010, 11:43:28 am
well said m8,
@golden gal - my friend took 991 ES imside and guess what? no problem! Chill, good luck :)
thx ........ sure lol :-[ :-[
Post by: The Golden Girl =D on May 04, 2010, 11:45:59 am
Nov 2004, paper2 , answer 6thx again
a) speed = distance / time
distance = 120-72 = 48.
time = 0830 - 0800 = 30 minutes = 0.5 hour
therefore speed = 48/0.5 = 96km/h
b) At 0900 hours, the distance covered is 0 because it is not moving (the line is constant at 40). Time = 1 hour. 0/1 = 0
Post by: Baladya on May 04, 2010, 11:46:26 am
Ok thats the right method..
still ill solve it for ya.
y = m2 - 4n2
y - m2 = -4n2
Dividing both by -4=
=
therefore
n =
long q, next up
O okay, i just didnt make the y- and bla bla. Thx
K about the Quadratic thing. How did u know its an isosceles traingle. I understood everything just need to know how its an isosceles..
Thx By the way :D
Post by: Ghost Of Highbury on May 04, 2010, 11:49:14 am
Post by: haris94 on May 04, 2010, 11:50:56 am
Post by: Baladya on May 04, 2010, 11:54:13 am
Nov 2004, paper2 , answer 6
a) speed = distance / time
distance = 120-72 = 48.
time = 0830 - 0800 = 30 minutes = 0.5 hour
therefore speed = 48/0.5 = 96km/h
b) At 0900 hours, the distance covered is 0 because it is not moving (the line is constant at 40). Time = 1 hour. 0/1 = 0
By the way speaking of calculators and this question...
My teacher told me a really cool trick in the calculator... If u have the (.,,,) button, you can use it to answer the questions that tell you to for example calculate the time of arrival. All you gotta do is put the hours(here 0830) like this: 08(press the button)30(press it)00(press), then - 08(press)00(press)00(press). It will give u the answer and u can change from decimels to hours and minutes by pressing the button (like the S<>D). By the way the first press is for hours, then min, then sec.
Hope u understood this cuz its really helpful :D ;D ;)
Post by: The Golden Girl =D on May 04, 2010, 11:57:11 am
By the way speaking of calculators and this question...
My teacher told me a really cool trick in the calculator... If u have the (.,,,) button, you can use it to answer the questions that tell you to for example calculate the time of arrival. All you gotta do is put the hours(here 0830) like this: 08(press the button)30(press it)00(press), then - 08(press)00(press)00(press). It will give u the answer and u can change from decimels to hours and minutes by pressing the button (like the S<>D). By the way the first press is for hours, then min, then sec.
Hope u understood this cuz its really helpful :D ;D ;)
ya mine said the same :P
Post by: Baladya on May 04, 2010, 11:58:12 am
anyone knows how to solve quadratic equations on a calci (casio fx series)
Ya. For example 2x^2+2x-2
press the mode button. then press 5(EQN) and choose 3 (ax^2+bx+c=0) write 2 ENTER 2 ENTER -2 ENTER. IT will give u the first answer. ENTER gives u the second answer :D. If anther example (diff numbers) just change the numbers...
Post by: Ghost Of Highbury on May 04, 2010, 11:59:27 am
do this,..
On-->3 times "mode"--> "1" (Eqn) --> press the "right arrow" --> "3" --> type th co-efficient of x3 nd press "=" -->
type th co-efficient of x2 nd press "=" --> type the co-efficient of x nd press "=" --> type the value of "d" i.e co-efficient of x0 and press "=".
U'll get an answer..press "=" 2 more times to find the other values
e.g -> a cubic equation --> ax3 + bx2 + cx + d
Post by: Saladin on May 04, 2010, 12:35:25 pm
I think the examiners in your school did not know that!
But to be on the safe side, do not use them! You gain no additional benefit in doing so. You will ALWAYS have to show your working!
Post by: Baladya on May 04, 2010, 02:31:33 pm
Post by: Vin on May 04, 2010, 02:46:59 pm
Post by: Baladya on May 04, 2010, 03:54:56 pm
If so then here is another useful calculator method for the pain-in-the-... questions :D ^^
Post by: Ghost Of Highbury on May 04, 2010, 04:00:17 pm
Post by: Baladya on May 04, 2010, 04:35:32 pm
Post by: Ghost Of Highbury on May 04, 2010, 04:37:45 pm
Post by: Baladya on May 04, 2010, 05:34:51 pm
In Student forum: yes xD.I just wanted to know why/how can i change my dp, add an email, signature, blabla. Cuz i can't manage to do it in Profile. Is it cuz m still a Newbie :'(?
Post by: Ghost Of Highbury on May 04, 2010, 05:46:15 pm
Post by: Baladya on May 04, 2010, 06:08:01 pm
go to profile -- > left side, under the "modify profile" header. check the options, edit ur profile.O i missed the Forum Information button :P
Post by: Adzel on May 04, 2010, 06:29:23 pm
Histograms.
Line graghs.
Transformation.
I want it ASAP
Thanks in advanced
Post by: Ghost Of Highbury on May 04, 2010, 06:40:16 pm
Post by: haris94 on May 04, 2010, 06:42:57 pm
Ya. For example 2x^2+2x-2
press the mode button. then press 5(EQN) and choose 3 (ax^2+bx+c=0) write 2 ENTER 2 ENTER -2 ENTER. IT will give u the first answer. ENTER gives u the second answer :D. If anther example (diff numbers) just change the numbers...
got it
Thanks :)
Post by: The Golden Girl =D on May 05, 2010, 11:49:20 am
thx in advance
Post by: DrEvil on May 05, 2010, 11:51:51 am
could anyone give me a link to nov oo paper 2 marking scheme ?......i really need it and i searched it for it everywhere in like 3-5 websites and i didn't find it .........i really need it ...plz give me the link ASAP!!
thx in advance
i don't think it is available...try out ur school library...
Post by: Ghost Of Highbury on May 05, 2010, 12:02:23 pm
here
http://www.scribd.com/doc/3182918/Math-Answers-P2-P4-1993-2003
pg 96
Post by: Vin on May 05, 2010, 12:11:02 pm
if u meant nov 2000 paper 2 answer scheme
here
http://www.scribd.com/doc/3182918/Math-Answers-P2-P4-1993-2003
pg 96
oh Thanks gr8!!
Post by: Baladya on May 05, 2010, 01:02:05 pm
find f^-1f(x)
Answer is x. Can u plz show me the steps?
Thnksssssss :) ^^
Post by: Vin on May 05, 2010, 01:11:35 pm
3
put 3x - 1 as x in eqn 1 ..u'll get it
(3x -1) - 1
-----------
3
= x
Post by: Baladya on May 05, 2010, 01:39:47 pm
Post by: haris94 on May 05, 2010, 01:51:43 pm
... but aren't u supposed to substitute first... like 3(3x-1)-1 cuz its f-1f(x) not ff-1(x)
they hv asked f-1f(x)
so u hv to substitute the value of f(x), that is 3x-1, in the equation f-1(x)
Post by: Baladya on May 05, 2010, 01:58:52 pm
Post by: haris94 on May 05, 2010, 02:25:43 pm
Post by: The Golden Girl =D on May 05, 2010, 03:17:03 pm
if u meant nov 2000 paper 2 answer scheme
here
http://www.scribd.com/doc/3182918/Math-Answers-P2-P4-1993-2003
pg 96
thx alot
Post by: The Golden Girl =D on May 05, 2010, 03:21:33 pm
it's question 18) part a) amd b) ...how do we get the numbers "cuz i saw the m.s. but i still haven't understood it yet , u see"
thx in advance
Post by: Ghost Of Highbury on May 05, 2010, 03:26:58 pm
Post by: The Golden Girl =D on May 05, 2010, 03:29:50 pm
copy paste the question, or upload the paper plz.
http://www.freeexampapers.com/FreeExamPapers.com_.php?__lo=SUdDU0UvTWF0aHMvQ0lFLzIwMDAgTm92L1BhcGVyIDIgTm92IDAwLnBkZg==
Post by: contraentry on May 05, 2010, 03:30:48 pm
Rearrange the formula to get : Class Width * Frequency Density = Frequency
For part (b) you may also make use of the aforementioned formula.
Post by: The Golden Girl =D on May 05, 2010, 03:33:12 pm
Frequency Density = Frequency / Class Width.
Rearrange the formula to get : Class Width * Frequency Density = Frequency
For part (b) you may also make use of the aforementioned formula.
i didn't get what u said abt part b)
Post by: Baladya on May 05, 2010, 03:39:48 pm
Post by: contraentry on May 05, 2010, 03:48:17 pm
part (d) & (e) of question 5, on the attached sheet.
Post by: Ghost Of Highbury on May 05, 2010, 03:57:03 pm
I have stumbled upon a slight issue in solving one of the Paper 4's, could someone please explain how to go about solving this ?
part (d) & (e) of question 5, on the attached sheet.
which year is this from?
Post by: Baladya on May 05, 2010, 04:01:05 pm
and also hard. I cant think of anyway u can find the sides...
Post by: The Golden Girl =D on May 05, 2010, 04:02:56 pm
it's november 2000 paper 2 ...question 21) part a) .......i just wanna know y do i have to do this "180-54" .....i just don't get this part
can someone plz answer me :-\
as for contraentry ..thx alot for the help abt the other question .......just to let u kno i really want to help but i gtg cuz mystudy group r comin over .... srry :-[
Post by: ksitna on May 05, 2010, 04:17:10 pm
11 b
13
p2 j2006
Post by: Ghost Of Highbury on May 05, 2010, 04:25:31 pm
hey how do i do ques
11 b
13
p2 j2006
11b)
Cross multiply
x = 4x + 12
12 = -3x
x = -4
13)
cross multiply
3x - 6 = 8x + 20
-5x = 26
x = -5.2
Post by: contraentry on May 05, 2010, 04:30:18 pm
which year is this from?
This is from November 1990 P4
@The golden girl: You're welcome!
You need to do the "180 - 54" because the question says it is an obtuse angle, and the Sine function proves : Sin 54 = Sin(180-54)
Moreover, 54 is not an obtuse angle, an obtuse angle is defined as an angle being greater than 90 and less than 180.
Post by: Baladya on May 05, 2010, 04:32:32 pm
By the way i have another question answer it for me ,plz!!
it's november 2000 paper 2 ...question 21) part a) .......i just wanna know y do i have to do this "180-54" .....i just don't get this part
can someone plz answer me :-\
as for contraentry ..thx alot for the help abt the other question .......just to let u kno i really want to help but i gtg cuz mystudy group r comin over .... srry :-[
Ya okay. Look in the question they said its OBTUSE. And the your answer will be 54. However 54 means it acute. So u have to 180-54. I dont know exactly why but as i said it has to do with being obtuse
Post by: Ghost Of Highbury on May 05, 2010, 04:32:48 pm
By the way i have another question answer it for me ,plz!!
it's november 2000 paper 2 ...question 21) part a) .......i just wanna know y do i have to do this "180-54" .....i just don't get this part
can someone plz answer me :-\
as for contraentry ..thx alot for the help abt the other question .......just to let u kno i really want to help but i gtg cuz mystudy group r comin over .... srry :-[
Ok if u solve it using the sine method. You get 54 degree. However they say its obtuse which means sine x = 0.809 , x =/= 54.
in such situations, u have to use the trigonometric rule sine x = sine 180-x rule to find any other angle whose sine is 0.809
thus, 180-54 = 126. sine 126 = 0.809
Answer : 126 (Obtuse)
Post by: Baladya on May 05, 2010, 04:34:26 pm
I guess contraentry was faster :D
Post by: contraentry on May 05, 2010, 04:42:58 pm
haha we all answered xD
I guess contraentry was faster :D
'Cause I'm a ninja... :P :P
Post by: ksitna on May 05, 2010, 05:13:24 pm
kk how do i do this one
A company makes two models of television.
Model A has a rectangular screen that measures 44 cm by 32 cm.
Model B has a larger screen with these measurements increased in the ratio 5:4.
(a) Work out the measurements of the larger screen.
Post by: Ghost Of Highbury on May 05, 2010, 05:14:48 pm
1.25 * 44 = 55
1.25 * 32 = 40
55, 40
Post by: Baladya on May 05, 2010, 05:52:48 pm
A similar model of the statue has a height of four centimetres.
(a) Calculate the volume of the model statue in cubic centimetres.
Anyone :D?
Post by: Ghost Of Highbury on May 05, 2010, 06:37:47 pm
I have stumbled upon a slight issue in solving one of the Paper 4's, could someone please explain how to go about solving this ?
part (d) & (e) of question 5, on the attached sheet.
Ok here goes the (d) part.
Let midpoint of the chord be G,perpendicular from centre bisects the chord AC.
Now AG = 1.8 m
Now two right angled triangles AOF and AGE are similar, therefore their corresponding sides will be proportional
OA/AG= AF/GE
2/1.8=5/GE
GE=(5*1.8)/2 = 4.5 m
CHeck the attached image.
e) Consider the triangle OGC. OG =
Let the point where GE intersects the circle be M.
MG = 2 + 0.87 = 2.87
Thus ME = 4.5 - 2.87 = 1.63
OE = ME + OM = 3.63
OD =
Consider the right angled triangle ODE. OE = 3.63, OD =
ED =
FE = ED = 3.97
FD = 8 (app.)
Area of trapezium = 0.5* (3.6+8)*4.5 = 26.1
Area of whole Shape = 26.1 + Area of the semi-circle ABC.
Area of semi-circle ABC = 2.913
Thus the area of the whole shape = 29cm^2
Post by: haris94 on May 05, 2010, 06:47:31 pm
A statue two metres high has a volume of five cubic metres.
A similar model of the statue has a height of four centimetres.
(a) Calculate the volume of the model statue in cubic centimetres.
Anyone :D?
V1/V2 = (l1/l2)3
so
5/v2 = (2/0.4)3
v2 = 5*(0.4)3
(2)3
v2 = 0.04m3
0.04*1000
=40 cm3
Post by: contraentry on May 05, 2010, 06:49:30 pm
Once again, thank you so much! :) :)
Post by: Ghost Of Highbury on May 05, 2010, 07:05:32 pm
Post by: Saladin on May 05, 2010, 07:06:50 pm
Post by: Baladya on May 05, 2010, 07:19:11 pm
V1/V2 = (l1/l2)3
so
5/v2 = (2/0.4)3
v2 = 5*(0.4)3
(2)3
v2 = 0.04m3
0.04*1000
=40 cm3
OMG HOW DID I FORGET THE RATIO THING ??? ??? Anyway thanks man ;)
Post by: haris94 on May 05, 2010, 07:24:33 pm
Post by: The Golden Girl =D on May 06, 2010, 06:03:16 am
This is from November 1990 P4
@The golden girl: You're welcome!
You need to do the "180 - 54" because the question says it is an obtuse angle, and the Sine function proves : Sin 54 = Sin(180-54)
Moreover, 54 is not an obtuse angle, an obtuse angle is defined as an angle being greater than 90 and less than 180.
thx again !!
Post by: The Golden Girl =D on May 06, 2010, 06:04:57 am
Ok if u solve it using the sine method. You get 54 degree. However they say its obtuse which means sine x = 0.809 , x =/= 54.
in such situations, u have to use the trigonometric rule sine x = sine 180-x rule to find any other angle whose sine is 0.809
thus, 180-54 = 126. sine 126 = 0.809
Answer : 126 (Obtuse)
i didn't know that such a rule "sin =180 - 54" can come in a traingle question.....that's y i didn't even think of this rule ..........thx !!
Post by: LM on May 06, 2010, 07:47:42 am
I have billion of question I don't understand...
Could you please help me?
here are the question...
1. Carla estimates the length of the wall to be 25 m and the height to be 2 m.Paolo tells her that the length is 25 m correct to the nearest 5 m and the height is 5 m correct to the nearest 10 centimetres. Complete the statements below.
(a) ............m ? length of the wall < ...........m
(b) ............m ? height of the wall < ...........m
and everytime this kind of question come up, I never understand hooq to do it....
2.
Post by: Snake on May 06, 2010, 08:23:52 am
1.9M=<Height of the wall<5.1M
That should be right
Post by: Dark Prince on May 06, 2010, 08:46:25 am
Q- Two men, John and Peter, can paint a house in 10 days. John alone can paint the house in 15 days. How long will Peter take to paint it alone?
Post by: Ghost Of Highbury on May 06, 2010, 09:11:51 am
10x + 150
--------- = 1
15x
10x + 150 = 15x
5x = 150
x = 150/5 = 30
30 days.
Im not sure abt this though
Post by: haris94 on May 06, 2010, 09:29:30 am
10/15 + 10/x = 1
Post by: Vin on May 06, 2010, 09:41:06 am
10/15 + 10/x = 1
10x + 150
--------- = 1
15x
10x + 150 = 15x
5x = 150
x = 150/5 = 30
30 days.
Im not sure abt this though
yup its right...i hav another method..
john n peter 10days => 1 house
1 day => 1/10 house
john in 1 day => 1/15
so, one day of john + peter = one day of john n peter together
1/15 + x = 1/10
(L.C.M)
1 + 15x
--------- = 1/10
15
1 + 15x = 15/ 10
15x = 15/10 -1
(LCM on right)
15x = 1/2
x = 1/30
peter paints 1/30 of house 1 one day...so he takes 30 days to paint one house :) :)
always try to convert any work to 1 day n solve..i find this method easy tho..dunno abt others.. :)
Post by: Vin on May 06, 2010, 09:44:25 am
can u pls explain how u got your first step:
10/15 + 10/x = 1
days for..(time taken for)
john+peter/john + john+peter/peter = 1 house
Post by: haris94 on May 06, 2010, 09:53:17 am
days for..(time taken for)
john+peter/john + john+peter/peter = 1 house
hmm...yea got it Thanks
nice method By the way
Post by: Baladya on May 06, 2010, 10:03:40 am
Post by: LM on May 06, 2010, 10:13:17 am
can you explain it steps by steps pleazzzz?
Post by: saleemsamer on May 06, 2010, 11:32:54 am
2.a.iv.
2.b.ii
and 10 f and g
can any1 plz explain thm to me o and one more thing can anybody upload how question's 4 answers will look like cuz in ms they don't show u anything
thx in advance :D
Post by: bashar1045 on May 06, 2010, 01:11:11 pm
first of all i need help in this question , June 2003 q5 part Bi and bii
and june 2005 q6 all of part bi
how do we find W and X ..? ???
Post by: bashar1045 on May 06, 2010, 01:18:20 pm
This isn't only in triangles. Its also in Sine and Cosine rule. Sometimes they ask u to write the two answers for sinx under for example 180.. search google for the sine and cosine 'curve' for maths and u will understand what m saying.
hey abdulrahman :) .. but the question involving sine curve or cosine curve are no more included in the recent years ..
Post by: Baladya on May 06, 2010, 01:50:28 pm
hey guys ,,
first of all i need help in this question , June 2003 q5 part Bi and bii
and june 2005 q6 all of part bi
how do we find W and X ..? ???
Hey sha5bar ;)
June 2003 doesnt even have bi and ii
for 2005:
bi) u already no the diameter of the pencil, so just multiply the diameter by 2 to find x and multiply by 6 to find w
bii)volume:wXxX18
biii)volume of pencils from a divided by volume in bii times 100
By the way Bashar, i found out that the calculator u have (fx991-EX) is not allowed...
Post by: bashar1045 on May 06, 2010, 02:09:24 pm
By the way Bashar, i found out that the calculator u have (fx991-EX) is not allowed...
[/quote]
thx ,, i have two calculators fx-911ES & Fx-82ES
and By the way our school dont even care about what type calculators we will bring .
Post by: Baladya on May 06, 2010, 02:18:05 pm
hehehe :P ya but what if someone from Cambridge comes :o. Play safe :D
By the way Bashar, i found out that the calculator u have (fx991-EX) is not allowed...
thx ,, i have two calculators fx-911ES & Fx-82ES
and By the way our school dont even care about what type calculators we will bring .
Post by: saleemsamer on May 06, 2010, 03:51:39 pm
Post by: PeaceMaker on May 06, 2010, 03:55:58 pm
Post by: ksitna on May 06, 2010, 05:21:09 pm
not sure though
Post by: nid404 on May 06, 2010, 05:29:30 pm
Post by: contraentry on May 06, 2010, 05:59:08 pm
2(a)(iv): Look at triangle 'X', its points have moved from triangle U, parallel to the Y -axis, yet its area remains the same as triangle U. Hence, it is a shear.
Now look at each individual point that has moved, (from U onto X) and hence determine the Shear factor, using the formula Shear factor = Distance a point has moved due to a shear (divided by) its distance from the invariant line. In a shear, the invariant line and parallel line are the same, hence, using the formula you get shear factor as 1.
Therefore the transformation can be described as: A shear with the Y axis invariant line and shear factor 1.
2b(ii) : This will be then inverse of the matrix of the shear in part 2(a)(iv). [Check this in the formula booklet]
10(f):substitute (n-1) in the previous equation's "n" place, and simplfy
I understood it now!
10(g): total of the numbers in row "n" = n(n2-n+1) + (total of n-1 even numbers)
From part (f): we know the total of n-1 even numbers is (n-1)n =n2-n
so now simplify and you should arrive at the answer in c(ii) = n3
Post by: Ghost Of Highbury on May 06, 2010, 06:19:23 pm
lets start by the sequence to find the total of the numbers. one of the example which were given is
(4 × 13) + 2 + 4 + 6
now the first number (4) is the row number.
the second digit (13) is the first number of that row
the last sequence (2+4+6) is the total of the first (n-1) even numbers, in this case the first (4-1) = 3 even numbers
---
The row number is 'n'
the first number of the row is determined by the formula
The last sequence is determined by
-
u just have to put them all together as this pattern "(4 × 13) + 2 + 4 + 6" to prove that it is equal to
--
heres how u do it
simplify to get
Hence Proved.
Post by: PeaceMaker on May 06, 2010, 07:10:38 pm
Post by: Ghost Of Highbury on May 06, 2010, 07:26:19 pm
Does anybody know what Paper 2 focuses on and what Paper 4 focuses on mostly? I dont want to waste my time studying chapters irrelevant to what they mostly focus/bring in paper 2/4.
There are no irrelevant chapters in maths. expect questions from every chapter in both the papers.
Post by: contraentry on May 06, 2010, 08:42:58 pm
Post by: PeaceMaker on May 07, 2010, 12:07:02 am
There are no irrelevant chapters in maths. expect questions from every chapter in both the papers.
Well, i didn't mean literally irrelevant (No point in making us study if they are not going to bring it, right?) What i meant was if the chapter was irrelevant in terms of paper 2. From what im seeing, paper 2 mostly has algebra, percentage, ratio, order/line of symmattry, matrices, the nth rule and sometimes graphs.
Post by: saleemsamer on May 07, 2010, 06:48:22 am
and im sorry but i still didnt get the shear can u plz show me on a diagram the points
and for question 4a any1?
sry if im askin 4 2 much ::)
and thx 4 ur hlp
Post by: The Golden Girl =D on May 07, 2010, 08:03:04 am
Well, i didn't mean literally irrelevant (No point in making us study if they are not going to bring it, right?) What i meant was if the chapter was irrelevant in terms of paper 2. From what im seeing, paper 2 mostly has algebra, percentage, ratio, order/line of symmattry, matrices, the nth rule and sometimes graphs.
of what i noticed from solvin alot of past papers of math both 2 and 4...is that what comes in paper 2 is random ....once they put the sequence chapter and in other times they don't .... etc..
as for paper 4 it has some chapters which my tutor said that they defenitly come among many random others!! ..ex: mensuration ..graph function "equations and drawing the graph" .....linear programing "is random" ...umm sequence .... percentage , ratio and tax ...etc..........
got it ?
hope i helped
Post by: PeaceMaker on May 07, 2010, 09:08:29 am
of what i noticed from solvin alot of past papers of math both 2 and 4...is that what comes in paper 2 is random ....once they put the sequence chapter and in other times they don't .... etc..
as for paper 4 it has some chapters which my tutor said that they defenitly come among many random others!! ..ex: mensuration ..graph function "equations and drawing the graph" .....linear programing "is random" ...umm sequence .... percentage , ratio and tax ...etc..........
got it ?
hope i helped
Yeah. Thank you for your time and i guess i'll study everything from start to finish just to be on the safe side.
Post by: saleemsamer on May 07, 2010, 09:51:15 am
and can sum1 plz explain questions 2a)iv and b)ii (same paper)
thx in advance :)
Post by: Dark Prince on May 07, 2010, 11:25:40 am
Post by: Vin on May 07, 2010, 11:51:18 am
hi guys can some1 post the diagram for oct/nov 09 p4 question 4a
and can sum1 plz explain questions 2a)iv and b)ii (same paper)
thx in advance :)
i'll try gimme some time.. ;)
Post by: Vin on May 07, 2010, 12:02:06 pm
i'll try gimme some time.. ;)
Post by: Vin on May 07, 2010, 12:05:54 pm
hi guys can some1 post the diagram for oct/nov 09 p4 question 4a
and can sum1 plz explain questions 2a)iv and b)ii (same paper)
thx in advance :)
a iv) shear, factor = -1 , y-axis invariant line
u should know the formula
shear = distance moved due to shear
----------------------------
perpendicular dist. frm invariant
Post by: Vin on May 07, 2010, 12:19:23 pm
hi guys can some1 post the diagram for oct/nov 09 p4 question 4a
and can sum1 plz explain questions 2a)iv and b)ii (same paper)
thx in advance :)
n also b) ii)
theres a great method my teacher taught me...
(y) x U = X
(a b) (-1 -4 -4 ) ( -1 -4 -4)
(c d) (1 1 3 ) = ( 2 5 7 )
multiply a b c d in matrix y to matrix U (they are the positions of the image, row 1 is x axis row 2 is y )
( (-a + b) (-4a+b) (-4a + 7b) )
( (-c+d ) (-4c +d) (-4c+ 7d) )
now solve any two equation my simultaneous method...
so, -a +b = -1 (because the position of this equation is corresponding to matrix "X", look for the colours)
-4a + b = -4
by solving u get a = 1 , b = 0
same for 'c' and 'd' ..u get d= 1 and c = -1
i dont expect u to understand but this method is really good n its really difficult for me to teach online..:(
read it n try to follow the steps while solving the paper u might get it...:) :)
Post by: Dark Prince on May 07, 2010, 01:03:36 pm
a iv) shear, factor = 1 , y-axis invariant line
u should know the formula
shear = distance moved due to shear
----------------------------
perpendicular dist. frm invariant
Actually i did this Q da sme waybut in da mark scheme da answer is Scale factor= -1......how is da scle factor -ve
Post by: Snake on May 07, 2010, 03:16:16 pm
Post by: Vin on May 07, 2010, 03:46:33 pm
Actually i did this Q da sme waybut in da mark scheme da answer is Scale factor= -1......how is da scle factor -ve
oh my bad... the image moves to the left is -ve and to the right is positive.. :)
sorry about that mistake..i'll amend it
Post by: Dark Prince on May 07, 2010, 06:03:13 pm
Post by: Vin on May 07, 2010, 07:32:58 pm
can u explain it .....y is da scale factoe -ve wen we move da image to left.....nd is this rule same 4 all quadrants? wat abt 3rd quadrant......wat if da image is on x-axis.....nd wat abt stretch( wen is its scale factor -ve).....thnkx.
actually even im kinda confused regarding this topic .. :-\
the thing is i saw this rule noted in my text book while referring it ..
my teacher might hav told it in class ..
i hav emailed her about this i should get her reply soon .. :)
Post by: astarmathsandphysics on May 07, 2010, 09:12:10 pm
Post by: Vin on May 08, 2010, 07:18:29 am
Thank you .. im looking forward to have them :)
Post by: PeaceMaker on May 08, 2010, 07:53:48 am
Post by: astarmathsandphysics on May 08, 2010, 07:57:22 am
Post by: Vin on May 08, 2010, 08:59:38 am
Could someone be kindly to explain to me the upper bounds and lower bounds in detail? Im kinda am confused about them, but if you have notes about them then feel free to pass them on to your fellow SF mate.
ALWAYS remember ..
for addition and multiplication ..
LB = LB + LB
LB = LB x LB
UB = UB + UB
UB = UB x UB
for subtraction or division .. (is different)
LB = LB - UB
LB = LB/UB
UB = UB - LB
UB = UB/LB :)
consider solving some sums u'll get them :).. these kinda ques usually appear in paper 2 .. (jus solved a couple of them few mins ago)
Post by: Dark Prince on May 08, 2010, 01:23:04 pm
actually even im kinda confused regarding this topic .. :-\
the thing is i saw this rule noted in my text book while referring it ..
my teacher might hav told it in class ..
i hav emailed her about this i should get her reply soon .. :)
thnkxx....
Post by: Fastal on May 08, 2010, 01:53:30 pm
Paper 4, IGCSE
2(d)(iii)
I don't understand how you find the invariant line.
Post by: Snake on May 08, 2010, 01:56:54 pm
Post by: Fastal on May 08, 2010, 02:02:13 pm
3(a)(iv)[2005 June Paper 4(Igcse)]
How do you find the invariant line for the shear?
I actually have this doubt with stretch and shear(finding invariant line), when the image and object share no points.
Post by: Vin on May 08, 2010, 03:35:13 pm
2005 Oct/Nov
Paper 4, IGCSE
2(d)(iii)
I don't understand how you find the invariant line.
it might take me a lot of time .. havta solve the whole ques!!
Post by: Vin on May 08, 2010, 04:08:31 pm
2005 Oct/Nov
Paper 4, IGCSE
2(d)(iii)
I don't understand how you find the invariant line.
About invariant lines .. for stretch, the transformation takes place perpendicular to the invariant line .. ;)
Post by: ksitna on May 08, 2010, 04:11:01 pm
x-3= 4
4 x-3
Post by: Vin on May 08, 2010, 04:19:20 pm
how to simplify
x-3= 4
4 x-3
sorry i didnt get the ques ???
Post by: @d!_†oX!© on May 08, 2010, 04:21:05 pm
(x-3)/4 = 4/(x-3)
then,
=> (x-3)(x-3) = 4*4
=> x2 -6x +9 = 16
=> x2 -6x -7 = 0
=> (x+1)(x-7) = 0
=> x = -1 , x = 7
Post by: PeaceMaker on May 08, 2010, 04:25:10 pm
ALWAYS remember ..
for addition and multiplication ..
LB = LB + LB
LB = LB x LB
UB = UB + UB
UB = UB x UB
for subtraction or division .. (is different)
LB = LB - UB
LB = LB/UB
UB = UB - LB
UB = UB/LB :)
consider solving some sums u'll get them :).. these kinda ques usually appear in paper 2 .. (jus solved a couple of them few mins ago)
I dont really get it. If you would solve me some questions from the past papers with the formula's you provided, it would be really helpful.
Post by: Vin on May 08, 2010, 04:25:19 pm
Post by: Vin on May 08, 2010, 04:26:17 pm
I dont really get it. If you would solve me some questions from the past papers with the formula's you provided, it would be really helpful.
why dont u post some papers ..
Post by: Fastal on May 08, 2010, 04:36:35 pm
lets say "_" got stretched, and the image also moved away, in this case where is the invariant line?-------
-> _ __
Post by: Ghost Of Highbury on May 08, 2010, 04:39:10 pm
Post by: Fastal on May 08, 2010, 04:43:13 pm
The base didn't change its shape. Thus, the x-axis is invariant.
but it can be y=1 axis too right?
Post by: Ghost Of Highbury on May 08, 2010, 04:53:38 pm
Post by: Fastal on May 08, 2010, 04:59:26 pm
Post by: Baladya on May 08, 2010, 05:07:51 pm
Post by: ksitna on May 08, 2010, 05:12:32 pm
is it,
(x-3)/4 = 4/(x-3)
then,
=> (x-3)(x-3) = 4*4
=> x2 -6x +9 = 16
=> x2 -6x -7 = 0
=> (x+1)(x-7) = 0
=> x = -1 , x = 7
yeah thts what i meant
thanks
but it said simplify as a fraction
i still dont know how to do it
Post by: PeaceMaker on May 08, 2010, 05:14:11 pm
Post by: @d!_†oX!© on May 08, 2010, 05:22:46 pm
yeah thts what i meantumm..ok, try this
thanks
but it said simplify as a fraction
i still dont know how to do it
(x-3)/4 = 4/(x-3)
=> (x-3)/4 - 4/(x-3)
=> x2 -6x -7 / 4x -12
Post by: Ghost Of Highbury on May 08, 2010, 05:28:05 pm
q7) 3<2x-5<7
3+5<2x<7+5
8/2<x<12/2
4<x<6
q6) 17.5*11.5 = 201.25
Post by: ksitna on May 08, 2010, 05:31:41 pm
umm..ok, try this
(x-3)/4 = 4/(x-3)
=> (x-3)/4 - 4/(x-3)
=> x2 -6x -7 / 4x -12
uh im sorry
i dont really get it
how did u get -7?
Post by: PeaceMaker on May 08, 2010, 05:32:10 pm
Post by: Fastal on May 08, 2010, 05:36:07 pm
uh im sorry
i dont really get it
how did u get -7?
i think its +9
Post by: @d!_†oX!© on May 08, 2010, 05:39:35 pm
uh im sorrysee, first u substracct and then take the lcm
i dont really get it
how did u get -7?
it is
+9-16 which is equal to -7
(x-3)/4 - 4/(x-3) = 0
then take lcm
so,
(x-3)(x-3) - 4*4 / 4x - 12 = 0
x2 -3x -3x +9 -16 / 4x-12 = 0
so the simplify and get
x2 - 6x -7 / 4x -12 = 0
Post by: Vin on May 08, 2010, 05:43:01 pm
uh im sorry
i dont really get it
how did u get -7?
(x-3) (x-3) - 16
------------------
4x -12
x2 -6x + 9 - 16
------------------
4x -12
x2 - 6x -7
------------------
4x -12
Post by: Vin on May 08, 2010, 05:47:13 pm
Ok guys i hav a doubt .. after a long time .. :P
Post by: ksitna on May 08, 2010, 05:52:17 pm
see, first u substracct and then take the lcm
it is
+9-16 which is equal to -7
(x-3)/4 - 4/(x-3) = 0
then take lcm
so,
(x-3)(x-3) - 4*4 / 4x - 12 = 0
x2 -3x -3x +9 -16 / 4x-12 = 0
so the simplify and get
x2 - 6x -7 / 4x -12 = 0
the mark scheme says
x2-6x+25/4(x-3) :/
Post by: Ghost Of Highbury on May 08, 2010, 05:53:47 pm
check if its correct in the ms.
sin x = -0.76
x = sin-1(0.76) = -50
x = 360-50 = 310
x = 180+50 = 230.
@ksitna - adi_toxic and vin1094 are correct. 4(x-3) = 4x-12. same hing
Post by: ksitna on May 08, 2010, 06:09:11 pm
310 degrees and 230 degrees
check if its correct in the ms.
sin x = -0.76
x = sin-1(0.76) = -50
x = 360-50 = 310
x = 180+50 = 230.
@ksitna - adi_toxic and vin1094 are correct. 4(x-3) = 4x-12. same hing
no i meant they got -7
not 25
Post by: Vin on May 08, 2010, 06:10:16 pm
Post by: Ghost Of Highbury on May 08, 2010, 06:22:37 pm
@ksitna - ohk, ill check
Post by: Ghost Of Highbury on May 08, 2010, 06:26:20 pm
Post by: ksitna on May 08, 2010, 06:38:54 pm
Post by: Fastal on May 08, 2010, 06:43:05 pm
(x-3/4) + (4/x-3)
so here its
x2 + 9 - 6x + 16/4x-12
so you get +25
Post by: @d!_†oX!© on May 08, 2010, 06:43:30 pm
90
S | A
180----------0/360
T | C
270
Read the above as follows before starting:
1) A=All +ve , S= Sin +ve , T=Tan +ve , C=Cos +ve
2) This shows the four quadrants, going anticlockwise from 0 to 90 to 180 270 to 360.
3) This means that any angle in a specific quadrant is +ve acc to 1)
So, now coming to your question, the question is talking about sin, which is +ve in the 1st and 2nd quadrant.
The angle already given to us is in the 1st quadrant, so now we know we will get the same value in the second quadrant in the 2nd quadrant (180-x) or the after 360 (360+x)
Taking -50 to be x
we have the other two angles as,
180-(-50) = 180+50 = 230
360+(-50) = 360-50 = 310
:D hope that helps, not specifically for this question, but in general.
Post by: idrees on May 08, 2010, 06:48:34 pm
its killing me! if someone could just explain the dynamics of this q .. how do i go about solving the question. thats all i need .. im really good at mensuration, i have just forgotten how to solve questions regarding rate of flow of water ..
June 2007 p4 Q7
Thanks a LOT!
Post by: Fastal on May 08, 2010, 06:52:43 pm
hey i really need help with this Q.
its killing me! if someone could just explain the dynamics of this q .. how do i go about solving the question. thats all i need .. im really good at mensuration, i have just forgotten how to solve questions regarding rate of flow of water ..
June 2007 p4 Q7
Thanks a LOT!
the question means that 0.3*1.2*3 m3 flows in 1 minute so 1 hour is 64.8 m3
Post by: PeaceMaker on May 08, 2010, 07:00:23 pm
they arent wrong, the ms cant be wrong, which paper is this q from??
If your talking to me, i said that i asked the wrong Paper i wrote 2003 when i really wanted the answers of those questions from paper 2005
Post by: Vin on May 08, 2010, 07:14:43 pm
I know you got this already, but i don't mind elaborating :P
90
S | A
180----------0/360
T | C
270
Read the above as follows before starting:
1) A=All +ve , S= Sin +ve , T=Tan +ve , C=Cos +ve
2) This shows the four quadrants, going anticlockwise from 0 to 90 to 180 270 to 360.
3) This means that any angle in a specific quadrant is +ve acc to 1)
So, now coming to your question, the question is talking about sin, which is +ve in the 1st and 2nd quadrant.
The angle already given to us is in the 1st quadrant, so now we know we will get the same value in the second quadrant in the 2nd quadrant (180-x) or the after 360 (360+x)
Taking -50 to be x
we have the other two angles as,
180-(-50) = 180+50 = 230
360+(-50) = 360-50 = 310
:D hope that helps, not specifically for this question, but in general.
Ohh cool !! hadta read it thrice tho but i get it.. Thanks .. :)
Post by: Fastal on May 08, 2010, 07:16:51 pm
i made it easier by doing the previous bits---see attached pictures
img010 is for 2(d)(iii) from 2005 november p4
3(a)(iv) is from 2005 june p4
Post by: Ghost Of Highbury on May 08, 2010, 08:09:27 pm
I know you got this already, but i don't mind elaborating :P
90
S | A
180----------0/360
T | C
270
Read the above as follows before starting:
1) A=All +ve , S= Sin +ve , T=Tan +ve , C=Cos +ve
2) This shows the four quadrants, going anticlockwise from 0 to 90 to 180 270 to 360.
3) This means that any angle in a specific quadrant is +ve acc to 1)
So, now coming to your question, the question is talking about sin, which is +ve in the 1st and 2nd quadrant.
The angle already given to us is in the 1st quadrant, so now we know we will get the same value in the second quadrant in the 2nd quadrant (180-x) or the after 360 (360+x)
Taking -50 to be x
we have the other two angles as,
180-(-50) = 180+50 = 230
360+(-50) = 360-50 = 310
:D hope that helps, not specifically for this question, but in general.
lol, gr8 u did, i was pretty bored to type it..By the way
just to add something here..v had a mnemonic to remember the All Sine tan cos.
its All silver tea cups.
all , sine cos tan. :D
Post by: Ghost Of Highbury on May 08, 2010, 08:31:26 pm
can we look at my questions now :)
i made it easier by doing the previous bits---see attached pictures
img010 is for 2(d)(iii) from 2005 november p4
3(a)(iv) is from 2005 june p4
sorry for the late reply.
heres 2)d)iii
work out the inverse first.
determinant - 1.5
(1/1.5 0 ) = (2/3 0)
( 0 1.5/1.5) (0 1)
now first, u have to learn this list of matrix transformations, dont learn them all, learn the imp. ones like shear , stretch, enlargement etc, heres it : https://studentforums.biz/index.php/topic,5575.msg167872.html#msg167872 (3rd post)
and this is what it says abt stretch
Stretch
1. x invariant wer k=scale factor (1 0)
(0 k)
2. y invariant wer k=scale factor (k 0)
(0 1)
now if u notice, out matrix is like the 2. one.
therefore, it means, that its stretch with y invariant and scale factor = k = 2/3
and abt the shear question, sry, im a little confused myself. will try to help asap/
Post by: ksitna on May 08, 2010, 08:45:10 pm
well i dont get this question either
A cylindrical glass has a radius of 3 centimetres and a height of 7 centimetres.
A large cylindrical jar full of water is a similar shape to the glass.
The glass can be filled with water from the jar exactly 216 times.
Work out the radius and height of the jar.
Post by: Ghost Of Highbury on May 08, 2010, 08:57:23 pm
so volume of jar = 216* 63Pi = 13608Pi cm3
since jar is similar shape to glass then ratio of height / radius of the jar = 7/3
let height of jar = h cm
h/r = 7/3
r/h = 3/7
r = 3h/7
volume of jar = Pi *(3h/7)2*h
= 9h2/49 * h * Pi
= ( 9/49)*h3* Pi
so (9/49)*h3* Pi = 13608Pi
h^3 = 13608*(49/ 9)
h = 42 => r = 42 * 3/7 = 18
r = 18 cm and h = 42 cm
Post by: ksitna on May 08, 2010, 09:14:31 pm
Post by: idrees on May 08, 2010, 09:40:04 pm
can someone please explain the question
june 2007 p4 q7
hey i really need help with this Q.
its killing me! if someone could just explain the dynamics of this q .. how do i go about solving the question. thats all i need .. im really good at mensuration, i have just forgotten how to solve questions regarding rate of flow of water ..
June 2007 p4 Q7
Thanks a LOT!
Post by: Vin on May 08, 2010, 09:52:44 pm
um i asked this Q .. really no one helped
can someone please explain the question
june 2007 p4 q7
sure .. gimme some time .. :)
Post by: Dibss on May 08, 2010, 10:14:13 pm
Quote
well i dont get this question either
A cylindrical glass has a radius of 3 centimetres and a height of 7 centimetres.
A large cylindrical jar full of water is a similar shape to the glass.
The glass can be filled with water from the jar exactly 216 times.
Work out the radius and height of the jar.
Quote
Volume of glass = Pi*r2*h = 63Pi
so volume of jar = 216* 63Pi = 13608Pi cm3
since jar is similar shape to glass then ratio of height / radius of the jar = 7/3
let height of jar = h cm
h/r = 7/3
r/h = 3/7
r = 3h/7
volume of jar = Pi *(3h/7)2*h
= 9h2/49 * h * Pi
= ( 9/49)*h3* Pi
so (9/49)*h3* Pi = 13608Pi
h^3 = 13608*(49/ 9)
h = 42 => r = 42 * 3/7 = 18
r = 18 cm and h = 42 cm
there's a simpler way if you'd like actually...
(ratio of lengths)^3 = ratio of volumes
ratio of volumes = 1:216 and if you find the cube root you get ratio of sides as 1:6
then you simply multiply each length by 3 and get
r= 3x6 = 18cm
h= 7x6 = 42cm
make sense?
Post by: Dibss on May 08, 2010, 10:15:19 pm
Quote
then you simply multiply each lengthsorry, typo... meant 6
Post by: Vin on May 08, 2010, 10:18:13 pm
um i asked this Q .. really no one helped
can someone please explain the question
june 2007 p4 q7
Got it !! quite easy ..
a) is quite direct ..
for such kinda ques wat i always do is look for the units .. for eq in this one..
they hav asked Calculate the number of cubic metres .. 3 measurements hav to be multiplied (this is jus a tip .. this is how i under the ques)
so for this vol = 0.3 m x 1.2 x 3 m/min x 60 (for 1 hour)
= 64.8 cm3
-----------------------------------
b) same method as the previous ..
first
vol = 0.8m x 1.2m x 15 m/min x 60
= 864 cm3
for % , difference is 864 - 64.8 = 799.2
per cent = diff/original x 100
= 799.2
--------- x 100
64.8
= 1230 %
-----------------------------------
c) firstly always remember to convert ur units to units asked in ques..
1.3 mm = 0.0013m
vol = pi rrh
2 = pi r2 x 0.0013
on solvin = 22.1 m
-----------------------------------
d) take the length as L ..
surface area = 50.4/0.12
= 420 m2
SA = (0.8 x L) + (1.2 x L) + (0.8 x L)
420 = 0.8L + 1.2L + 0.8L
420 = 2.8 L
L = 150m .. done !! :)
Post by: $H00t!N& $t@r on May 08, 2010, 10:50:27 pm
Thanks in advance!
Post by: Dibss on May 08, 2010, 10:56:36 pm
do you mean sine/cosine rules by any chance?
Post by: $H00t!N& $t@r on May 08, 2010, 11:05:46 pm
do you need this for math or add math since i can't seem to remember any sine/cosine curve qs in math past papers...
do you mean sine/cosine rules by any chance?
I need it for math (0580). actually there are many questions on this but i dont seem to uderstand them. there isnt much in the text book either... I dont mean the sine and cosine rule used in triangles. Apparently, there are sine and cosine curves. do you have any idea on those?
Post by: Dibss on May 08, 2010, 11:22:57 pm
Post by: $H00t!N& $t@r on May 08, 2010, 11:34:14 pm
yep there are those :)) alright give me an example of a qs from past papers an we'll see if i can use that to explainIn fact one example of such questions is in this thread (page 13). It is solved but i dont grab the concept. Could you help me with that? :-\
Post by: Dibss on May 09, 2010, 12:20:29 am
if you draw a circle and divide into quarters or four 'quadrants' it looks something like below:
90
S | A
180----------0/360
T | C
270
each quadrant is labelled to represent what is positive in that quadrant:
1) A=All +ve , S= Sin +ve , T=Tan +ve , C=Cos +ve
2) This shows the four quadrants, going anticlockwise from 0 to 90 to 180 270 to 360.
you can test this out to familiarise yourself with it. do sin or cos or tan of any number between 0-90 on your calc and you'll get a positive answer.
do sin of any no from 90-180--> positive
tan of any no form 180-270--> positive
cos of any no form 270-360-->positive
ok. the actual question:
a)
sinx=sin 50
x=50degrees
they want the angle between 90 and 180 that'll give you the same answer. The angle already given to us is in the 1st quadrant, so now we know we will get the same value in the 2nd quadrant with (180-x)
180-50=130degrees
ok i just realised this might be difficult to understand without a diagram if you haven't done this before :/
b)sinx=-sin50
sine is negative in 3rd and 4th quadrants
180+50=230
360-150=310
i'm really sorry if i haven't explained it clearly... hope it helps a little
Post by: Fastal on May 09, 2010, 05:53:10 am
sorry for the late reply.
heres 2)d)iii
work out the inverse first.
determinant - 1.5
(1/1.5 0 ) = (2/3 0)
( 0 1.5/1.5) (0 1)
now first, u have to learn this list of matrix transformations, dont learn them all, learn the imp. ones like shear , stretch, enlargement etc, heres it : https://studentforums.biz/index.php/topic,5575.msg167872.html#msg167872 (3rd post)
and this is what it says abt stretch
Stretch
1. x invariant wer k=scale factor (1 0)
(0 k)
2. y invariant wer k=scale factor (k 0)
(0 1)
now if u notice, out matrix is like the 2. one.
therefore, it means, that its stretch with y invariant and scale factor = k = 2/3
and abt the shear question, sry, im a little confused myself. will try to help asap/
so its a MUST to learn all the transformation matrices, theres no other way?
and about the shear question, please help :)
Post by: PeaceMaker on May 09, 2010, 05:59:18 am
Post by: Fastal on May 09, 2010, 06:22:19 am
Paper 2 2005 May/june Q) 2, 6, 13, 14b, 17. I don't understand please explain and again, thanks!
i have a doubt in 14b tooh
Post by: astarmathsandphysics on May 09, 2010, 06:33:28 am
Post by: Meticulous on May 09, 2010, 06:42:41 am
Paper 2 2005 May/june Q) 2, 6, 13, 14b, 17. I don't understand please explain and again, thanks!
Q2: sin5=h/3.17.....h=3.17*sin5
Q6: using triangle PBQ, PB=BQ= 4 cm..now use pythagoras
Q13: Easy. Count the dots first, then get the nth term.
Q14 b: % increase= (new value-old value)/old value x 100%
Q17: it says t=no of hours after midday, so at midday t=0..substitute 0 into the equation.
Post by: Monica on May 09, 2010, 07:01:14 am
Sin5= opp/hyp = h/3.17
Q6) Each side of ABCD is 8 cm and each point of PQRS is the mid point of ABCD, thus PB=4 and BQ=4.
Q14) Percentage increase= Increase/ actual *100.
310 000 - 62 000 / 62 000 = 4*100 = 400%
Post by: Fastal on May 09, 2010, 07:49:13 am
Post by: PeaceMaker on May 09, 2010, 08:16:33 am
Post by: Fastal on May 09, 2010, 08:28:57 am
a) you can see in the diagram that it increases by three thus
Pattern number|1|2|3|4|
Number of dots|5|8|11|14|
b)use the forumula
an=a1 +(n-1)d[d is the difference, and a1 is the first term]
an=5+(n-1)3
an=5+3n-3
an=3n+2
c)subsitute formula here
3*60+2=182
d)subsitute again
89=3n+2
thus n=29
Post by: PeaceMaker on May 09, 2010, 08:38:43 am
Post by: Vin on May 09, 2010, 09:36:08 am
SOMEONE PLEASE
Its clearly shear .. y axis invariant line .. im a lil confused about factor .. i think its 0.5 .. check in the ms ..
Post by: Fastal on May 09, 2010, 09:42:41 am
Its clearly shear .. y axis invariant line .. im a lil confused about factor .. i think its 0.5 .. check in the ms ..
how do you know about invariant line?
Post by: Vin on May 09, 2010, 09:45:16 am
the image always moves perpendicular to the invariant .. here the image moves to the right if u turn the page 90o aticlockwise u can see the image has moved exactly upwards or perpendicular .. :)
Post by: Ghost Of Highbury on May 09, 2010, 09:51:51 am
Post by: Vin on May 09, 2010, 09:55:42 am
i think its x axis .. ya ur right .. always get confused with such kinda sums ..!! can u tell me how can u be sure wid the invariant line ??
Post by: Ghost Of Highbury on May 09, 2010, 09:58:18 am
@astar - answer this doubt, it can be anything parallel to x-axis rite? but if it is , v'll get different shear factors..plz help.
Post by: astarmathsandphysics on May 09, 2010, 09:58:57 am
Post by: Fastal on May 09, 2010, 10:05:04 am
2005 june 3(a)(iv) paper 4 IGCSE
im confused abt it too, i know its something parallel to x-axis or the x-axis...x-axis because the point parallel to it dont change in shape, or move...
@astar - answer this doubt, it can be anything parallel to x-axis rite? but if it is , v'll get different shear factors..plz help.
exactly, you would get different shear factors
Post by: Fastal on May 09, 2010, 11:34:19 am
Post by: Ghost Of Highbury on May 09, 2010, 11:44:51 am
i think this is how you do it, BUT what if there was no x and y axis in the graph.
Yes it can be done in the matrix form.
And a graph doesn't exist without the axes. Cartesian plane, rather.
Post by: PeaceMaker on May 09, 2010, 11:50:23 am
Post by: Vin on May 09, 2010, 11:56:20 am
Post by: PeaceMaker on May 09, 2010, 12:04:02 pm
Post by: Fastal on May 09, 2010, 12:44:22 pm
why is the scale factor -ve???
i know this was discussesd before and someone said it moved left, but its moving right here, right?
Post by: Ghost Of Highbury on May 09, 2010, 01:23:32 pm
Post by: thenewkid™ on May 09, 2010, 01:25:13 pm
Post by: Fastal on May 09, 2010, 01:39:16 pm
its vertically left.doesent that depend on how you look at it?
i dont get it, whats vertically left?
Post by: thenewkid™ on May 09, 2010, 01:50:28 pm
Post by: Vin on May 09, 2010, 01:53:15 pm
youre supposed 2 decide if it's left or right with the invariant line. im trying 2 attach the solved 1 but i am nt able 2 any suggestions. im kinda new here dont knoe what 2 do?
i suppose u dont hav a scanner .. do u hav a webcam / camera ..?? lol i dont hav a scanner so i use my webcam !! :) :)
or jus simply type it !! :)
Post by: bilalasad_4660 on May 09, 2010, 01:54:34 pm
thnaks in advance. :)
Post by: @d!_†oX!© on May 09, 2010, 01:56:24 pm
See, thenewkid, when you click on "reply" in the bottom of the page, the window opens
now under the area given to type, oon the left there is an option "additional options..."
click on that and then attach :)
Post by: thenewkid™ on May 09, 2010, 01:58:46 pm
Post by: Vin on May 09, 2010, 02:01:46 pm
hey can anyone help me on question 10 june 2008 paper 2 ..
thnaks in advance. :)
vol = 216 times
k= cube root [ 216]
k = 6
k = r/3
6 x 3 = r
r = 18
same way for height .. h = 6 x 7 = 42
remember always .. for vol k is k3 and area k2
Post by: Dibss on May 09, 2010, 02:02:18 pm
Quote
hey can anyone help me on question 10 june 2008 paper 2s08qp2q10
(ratio of sides)3 = ratio of volumes
ratio of volumes is 1:216
so ratio of sides should be cube root of 1:216
ratio of sides= 1:6
to get lengths, multiply by 6
r=3x6=18cm
h=7x6=42cm
hope that helps!
(sorry VIN, didn't realise you answered already)
Post by: thenewkid™ on May 09, 2010, 02:15:16 pm
Quote
i suppose u dont hav a scanner .. do u hav a webcam / camera ..?? lol i dont hav a scanner so i use my webcam !! Smiley Smiley
or jus simply type it !! Smiley
any ways tk the invariant line as x=-1. the corner (-4,3) moves 4 spaces to the right along the invariant line and it is 3 spaces above the line.
i think this is correct bcause we had gotten a similar question in our schl exams and the teacher had told us this
Post by: Fastal on May 09, 2010, 03:04:43 pm
any ways tk the invariant line as x=-1. the corner (-4,3) moves 4 spaces to the right along the invariant line and it is 3 spaces above the line.
i think this is correct bcause we had gotten a similar question in our schl exams and the teacher had told us this
what?
Post by: Vin on May 09, 2010, 03:15:28 pm
s08qp2q10
(ratio of sides)3 = ratio of volumes
ratio of volumes is 1:216
so ratio of sides should be cube root of 1:216
ratio of sides= 1:6
to get lengths, multiply by 6
r=3x6=18cm
h=7x6=42cm
hope that helps!
(sorry VIN, didn't realise you answered already)
oh thts ok ..
Post by: Adzel on May 09, 2010, 04:33:31 pm
Post by: Monica on May 09, 2010, 05:01:22 pm
Post by: Adzel on May 09, 2010, 05:05:38 pm
Thanks...
Post by: Hesham Mhd on May 09, 2010, 05:06:45 pm
Post by: Ghost Of Highbury on May 09, 2010, 05:09:35 pm
3x -2 = 40
3x = 42
x= 14
6) a)120 - 72 = 48/0.5 = 96km/h
b) 0 km/h as only time is increasing not distance.
@hesham - post the link plz
Post by: Adzel on May 09, 2010, 05:13:58 pm
Post by: -Cornea on May 09, 2010, 05:16:06 pm
32=2^2n
2^5=2^2n
power are equal then
5=2n
n=5/2
ii)cube root of (1/8)=1/2
1/2=2^q
2^-1=2^q
consequently..q=-1
Post by: -Cornea on May 09, 2010, 05:22:47 pm
draw the paralleogram and consequently u will get the third side
A=(1,1) B=(4,6) C=(8,6) then u will get that D=(5,1)
use the rule =
square root of any 2 points let's take (4,6) and (1,1)
square root of (4-1)^2+(6-1)^2
square root of (3)^2+(5)^2
square root of 9+25
square root of 34
Answer=5.83
(Tht's the third question)
Post by: -Cornea on May 09, 2010, 05:23:37 pm
Post by: Hesham Mhd on May 09, 2010, 05:28:05 pm
Post by: -Cornea on May 09, 2010, 05:29:18 pm
Post by: Ghost Of Highbury on May 09, 2010, 05:32:38 pm
Post by: Vin on May 09, 2010, 05:35:37 pm
Whoa a lot has happened here .. :P
Post by: Vin on May 09, 2010, 05:48:24 pm
cant find the link sry, can yu read it plz?
You can find every paper on earth on www.freeexampapers.com .. !! ;)
Post by: Hesham Mhd on May 09, 2010, 05:51:10 pm
Post by: -Cornea on May 09, 2010, 07:09:39 pm
Post by: Adzel on May 09, 2010, 07:26:56 pm
Post by: Malak on May 09, 2010, 09:57:23 pm
Q7 b
Q11 - Can anyone explain how to get the answer ???
q18 b
Thx
Post by: -Cornea on May 09, 2010, 10:10:30 pm
now it's f^-1(x) so replace the y by 1 instead of replacing x because it's inverse
so it will be:
1=10^x
Anything to the power of zero =1
so x =0
listen u just need to find the perimeter of the shape
4*4 i.e(4+4+4+4) +2*pie*1.2 i.e(4*0.25*2*pie*1.2)
i guess the answer will be 23.5 approximatly it's 24 ppl (or if u want to add this half person :P)
Post by: Vin on May 09, 2010, 10:32:02 pm
(x-2)-1/2
------
(22)-1/2
x1
----
2-1
= 2x
Post by: -Cornea on May 09, 2010, 10:34:21 pm
=(x^27*2/3)/(27^2/3)
=(x^9*2)(divide by 3) (cube root of 27 =3 square it =9)
so it will be (x^18/9)
as27^2/3 means cubic root and then squaring it
Post by: Malak on May 09, 2010, 10:38:53 pm
Post by: Malak on May 09, 2010, 10:57:56 pm
f(x) = 3x - 1
Find. in its simplest form
F^-1f(x)
In ms the answer is x how ???
Post by: astarmathsandphysics on May 09, 2010, 11:12:25 pm
y=3x-1 so x=(y+1)/3 so f^(-1)( f(x))=(f(x)+1)/3=(3x-1+1)/3=x
Post by: Vin on May 09, 2010, 11:15:13 pm
3
put 3x - 1 as x in eqn 1 ..u'll get it
(3x -1) - 1
-----------
3
= x
Post by: SEL123 on May 10, 2010, 05:41:42 am
I asked my tutor and he said for IGs the invariant like is ALWAYS either the x-axis or the y-axis...
To someone who has practiced past papers
Is that true??
Post by: Fastal on May 10, 2010, 05:52:03 am
listen when u do f(x) u remove the X and replace it by the number given
now it's f^-1(x) so replace the y by 1 instead of replacing x because it's inverse
so it will be:
1=10^x
Anything to the power of zero =1
so x =0
listen u just need to find the perimeter of the shape
4*4 i.e(4+4+4+4) +2*pie*1.2 i.e(4*0.25*2*pie*1.2)
i guess the answer will be 23.5 approximatly it's 24 ppl (or if u want to add this half person :P)
i dont understand the function part.
and i still dont get how its vertically left for that shear question in 09November paper 4
Post by: $H00t!N& $t@r on May 10, 2010, 08:20:24 am
i dont understand the function part.
The function given to you is: f(x)= 10^x
The question says: write down the value of f^-1(1)
Take the 1 in the bracket from f^-1(1) and put it on the other side
So now it becomes 1= 10^x
One of the law in indices is the zero index law which says that any number raised to the power of 0 is equal to 1
After rearranging we have 1 as the answer so that means that 10 is raised to 0
Therefore x=0
Hope that helps! :)
Post by: Fastal on May 10, 2010, 08:24:26 am
Take the 1 in the bracket from f^-1(1) and put it on the other side
So now it becomes 1= 10^x
i dont understand this part, i get everything else
Post by: -Cornea on May 10, 2010, 08:52:44 am
Post by: $H00t!N& $t@r on May 10, 2010, 09:12:04 am
i dont understand this part, i get everything else
Look, in the question before this (7a) the question was f(0.5) so u replace the x in f(x)=10^x with o.5 and you get 3.16
However, this is not the case in the second one. Here you're meant to find the inverse f^-1 (1)
so it will be the other way round. The 1 in the bracket (f^-1 (1)) will be replaced with f(x) in f(x)=10^x
giving you 1= 10^x
If you still dont understand can you please specify what is it that you dont understand
Post by: -Cornea on May 10, 2010, 09:55:02 am
Post by: Fastal on May 10, 2010, 10:03:54 am
Look, in the question before this (7a) the question was f(0.5) so u replace the x in f(x)=10^x with o.5 and you get 3.16
However, this is not the case in the second one. Here you're meant to find the inverse f^-1 (1)
so it will be the other way round. The 1 in the bracket (f^-1 (1)) will be replaced with f(x) in f(x)=10^x
giving you 1= 10^x
If you still dont understand can you please specify what is it that you dont understand
hmm, we have a different way of finding inverse in school
suppose f(x)=2x+1
than f-1(x) is replace by y
y=2x+1(y and x are then switched)
x=2y+1
thus y=(x-1)/2
and f-1(x)=(x-1)/2
so can you tell me how to do it this way what is F-1(x) when f(x)=10x
Post by: -Cornea on May 10, 2010, 10:13:09 am
but if it's like this question instead of removing x remove y
listen f(x)---> remove x
f^-1--->opposite remove (y)
Got it:D
Post by: princess12 on May 10, 2010, 10:33:22 am
Post by: PeaceMaker on May 10, 2010, 10:34:26 am
Post by: -Cornea on May 10, 2010, 10:34:57 am
Post by: princess12 on May 10, 2010, 10:37:25 am
Post by: -Cornea on May 10, 2010, 10:44:10 am
4+5
--------
6
=9/6
3/2
so x=3
ii)5/3 / 3/y =40/9
so change the division sign into multiplication
5/3*y/3=40/9
so it will be 5y/9=40/9
9(5y)=9(40)
40y=360
y=9
Got it ;D
Post by: -Cornea on May 10, 2010, 10:46:25 am
0.5--->33
7.2--x
Post by: Malak on May 10, 2010, 10:50:50 am
can any one explain me 2,4,5 in oct 2006 please ??? ??? ???
Q2: 12 + 15 = x
------- ---
18 2
27 = x
---- ---
18 2
x= 2(3/2)
x= 6/2
x= 3
B-ii
5 Y 40
-- * -- = ---
3 3 9
5y 40
-- = --
9 9
45y = 360
y = 8
^^ Princess....I guess u did some mistake with multiplying :P 9(5) = 45 :)
Post by: Malak on May 10, 2010, 10:56:27 am
so
8 * 60 = 480
Now find the upper and lower bond
Upper: 475
Lower 485
She sleeps 30 nights so
475 * 30 = 14250 And thn divide by 60 to convert into hours = 237.5
485 * 30 = 14550 divide by 60 again = 242.5
237.5 < T < 242.5
-
Post by: PeaceMaker on May 10, 2010, 11:03:03 am
Does anyone have a brief summary or notes of the angles and shapes?I mostly get confused with these questions so if anyone has notes or could explain to me briefly, i would be really greatfull.
Also, for the lower and upper bounds. :D
Post by: astarmathsandphysics on May 10, 2010, 11:10:17 am
http://www.astarmathsandphysics.com/o_level_maths_notes/o_level_maths_notes_angles_in_polygons.html
Post by: princess12 on May 10, 2010, 11:15:57 am
Post by: -Cornea on May 10, 2010, 12:11:22 pm
Post by: PeaceMaker on May 10, 2010, 12:49:00 pm
Like this?
http://www.astarmathsandphysics.com/o_level_maths_notes/o_level_maths_notes_angles_in_polygons.html
Yes, thank you so much! :D +REP
Post by: holtadit on May 10, 2010, 01:12:05 pm
In less than 24 Hours the Physics Paper 6 and other IGCSE examinations will commence. Once this examination is over:
a) You MUST WAIT 24 HOURS before any discussions can take place.
b) ALL DISCUSSIONS must be held in the following thread : https://studentforums.biz/index.php/topic,7273.0.html
Good Luck to You All.
Post by: holtadit on May 10, 2010, 02:37:24 pm
Can someone give me a site that explains the characteristics of all the shapes that are usually asked in maths.
Like squares, parallelograms, rhombus, kites etc.
Thank You !
Post by: Baladya on May 10, 2010, 02:50:48 pm
Okay, this is quite embarassing. :P
Can someone give me a site that explains the characteristics of all the shapes that are usually asked in maths.
Like squares, parallelograms, rhombus, kites etc.
Thank You !
http://www.mathsisfun.com/geometry/plane-geometry.html (http://www.mathsisfun.com/geometry/plane-geometry.html)
I really like this site (has everything). Just choose the topic under (General)
By the way the exam is after tommorow noob ;D
Post by: holtadit on May 10, 2010, 03:47:08 pm
http://www.mathsisfun.com/geometry/plane-geometry.html (http://www.mathsisfun.com/geometry/plane-geometry.html)
I really like this site (has everything). Just choose the topic under (General)
By the way the exam is after tommorow noob ;D
This is your first warning !
There is no need to call me or anyone else a NOOB - it is derogatory and has negative connotations.
Please make sure to remain polite when using the forum.
As a matter of fact I am revising for my math exam since I am finished with physics.
Post by: Vin on May 10, 2010, 05:09:38 pm
That should be a lesson !! :P
Post by: Baladya on May 10, 2010, 06:13:09 pm
This is your first warning !
There is no need to call me or anyone else a NOOB - it is derogatory and has negative connotations.
Please make sure to remain polite when using the forum.
As a matter of fact I am revising for my math exam since I am finished with physics.
wowowwo WTH u kidding me?? Its the first time i see a guy getting angry when i "joke" with him saying the word "noob" when the site in the first place uses it (newbie) for new guys. If u don't like it fine, but its weird cuz i call all my friends noob and they call me noob for fun (either in real life or internet friends...)
Post by: Monica on May 10, 2010, 08:27:01 pm
Post by: Fastal on May 11, 2010, 07:22:22 am
Post by: Adzel on May 11, 2010, 07:59:11 am
Post by: The Golden Girl =D on May 11, 2010, 08:01:47 am
Post by: Fastal on May 11, 2010, 08:06:44 am
paper 4 09 nov, 2(a)(iv)
why is the scale factor -ve???
i know this was discussesd before and someone said it moved left, but its moving right here, right?
how does this question move vertically left.
Post by: thenewkid™ on May 11, 2010, 08:08:58 am
Oct/Nov 2008 p2 q5 variant 1
Thanks
Post by: thenewkid™ on May 11, 2010, 08:13:22 am
Thanks
Post by: thenewkid™ on May 11, 2010, 08:35:50 am
Post by: Ghost Of Highbury on May 11, 2010, 08:58:57 am
Post by: Adzel on May 11, 2010, 09:14:07 am
Q11, Q14 (b), Q16 (c), Q17 (c)....Thanks in advance.
Post by: thenewkid™ on May 11, 2010, 09:15:32 am
Thanks
Post by: Adzel on May 11, 2010, 09:25:39 am
here u go
Thanks
ANS Q6: x = sin-1 0.86603
= 60
i.e. 180-60 = 120
Post by: Adzel on May 11, 2010, 09:30:53 am
Post by: thenewkid™ on May 11, 2010, 09:35:15 am
Post by: Adzel on May 11, 2010, 09:37:18 am
http://www.xtremepapers.net/CIE/index.php?dir=Cambridge%20IGCSE/0580%20-%20Mathematics/&file=0580_s02_qp_2.pdf (http://www.xtremepapers.net/CIE/index.php?dir=Cambridge%20IGCSE/0580%20-%20Mathematics/&file=0580_s02_qp_2.pdf)
Q11, Q14 (b), Q16 (c), Q17 (c)....Thanks in advance.
anyone?...
Post by: Ghost Of Highbury on May 11, 2010, 09:40:08 am
(v+1)T = 5
v+1 = 5/t
V = 5/T -1
14b) assume y= -2
do the calculations, arrange them in order
q16c) f(x) = x^1/3
y = x^1/3
x = y^1/3
x^3 = y
f-1(x) = x^3
q17c) Inner circle = 2PIr
outer circle = 2*pi*4r = 8PIr
total = 10PIr
Post by: Adzel on May 11, 2010, 09:44:10 am
11) T = 5/(v+1)
(v+1)T = 5
v+1 = 5/t
V = 5/T -1
I did that but the mark scheme says 5-T/T ???
Post by: Vin on May 11, 2010, 09:47:20 am
I did that but the mark scheme says 5-T/T ???
Is it
5-T
----
T
ur saying ..?
Post by: Ghost Of Highbury on May 11, 2010, 09:47:45 am
I did that but the mark scheme says 5-T/T ???
same thing
Post by: Ghost Of Highbury on May 11, 2010, 09:51:03 am
11) T = 5/(v+1)
(v+1)T = 5
v+1 = 5/t
V = 5/T -1
14b) assume y= -2
do the calculations, arrange them in order
q16c) f(x) = x^1/3
y = x^1/3
x = y^1/3
x^3 = y
f-1(x) = x^3
q17c) Inner circle = 2PIr
outer circle = 2*pi*4r = 8PIr
total = 10PIr
ok answered all, check the ms and let me know if any silly errors..
Post by: Ghost Of Highbury on May 11, 2010, 09:55:04 am
Locus;
are u sure abt this?
Post by: Vin on May 11, 2010, 09:57:07 am
ok answered all, check the ms and let me know if any silly errors..
yup all correct!! :)
Post by: PeaceMaker on May 11, 2010, 09:58:23 am
Post by: Vin on May 11, 2010, 10:00:57 am
Keep ur cool and hope the papers easy .. even im not tht good at maths n im tryin to do the same !! .. :)
Post by: princess12 on May 11, 2010, 10:04:43 am
??? ??? ???
Post by: Ghost Of Highbury on May 11, 2010, 10:08:20 am
180 - 60 = 120 degree.
Post by: Vin on May 11, 2010, 10:08:26 am
oct/nov 2008 p2 q6
??? ??? ???
sin-1 (0.86603)
should get 60 .. or 120 :)
Post by: Ghost Of Highbury on May 11, 2010, 10:08:52 am
sin-1 (0.86603)
should get 60 .. :)
and 120.
The All Silver Tea Cups rule :P
Post by: Vin on May 11, 2010, 10:11:26 am
and 120.
The All Silver Tea Cups rule :P
ya i was in a hurry .. n also didnt see u'd alredy posted .. i hate it wen tht message appears ..n i dont even bother to look down .. :P
By the way wer were u yest ?? tons on ques ware booming at the physics thread .. :)
Post by: Ghost Of Highbury on May 11, 2010, 10:12:48 am
i was watching the premier league highlights..with my friends.. :)
Post by: Adzel on May 11, 2010, 10:18:05 am
14b) assume y= -2
do the calculations, arrange them in order
I got: y3 < y2 < y0 < y-1
but mark scheme says: y3 < y-1 < y0 < y2
Post by: Adzel on May 11, 2010, 10:32:35 am
Post by: thenewkid™ on May 11, 2010, 10:33:18 am
Thanks
Post by: Ghost Of Highbury on May 11, 2010, 10:39:08 am
I got: y3 < y2 < y0 < y-1
but mark scheme says: y3 < y-1 < y0 < y2
ur way : -8 < 4 < 1 < -0.5 = incorrect
ms way : -8 < -0.5 < 1 < 4 = correct
check ur calculations again :)
(-2)^3 = -8
(-2)^2 = 4
Post by: Baladya on May 11, 2010, 10:44:36 am
For upper bound we minus 6.5 minus 3.5 and for lower bound 5.5 - 4.5?
Thanks
Post by: Adzel on May 11, 2010, 10:45:03 am
------- = -------- = 320 cm3
s 23
(b) s 32
------- = -------- = 567 cm2
252 22
Post by: Adzel on May 11, 2010, 10:47:24 am
ur way : -8 < 4 < 1 < -0.5 = incorrect
ms way : -8 < -0.5 < 1 < 4 = correct
check ur calculations again :)
(-2)^3 = -8
(-2)^2 = 4
oops I forgot to put the brackets...thanks
Post by: Ghost Of Highbury on May 11, 2010, 10:48:29 am
Answer this one please too; +explaination
attached.
PQS = 80 degree.
Angle PQS = Angle PRS
the chord circumference rule.
QPR = 180 - 80 - 33 = 67 degree. (Angle Sum property)
PSQ => PXS = 147 (180-33). PSX = 180 - 147 - 21 = 12 degree.
Post by: Adzel on May 11, 2010, 10:49:46 am
If we want to calculate lower and upper bound of lets say 6-4.
For upper bound we minus 6.5 minus 3.5 and for lower bound 5.5 - 4.5?
Thanks
...to the nearest what?
Post by: astarmathsandphysics on May 11, 2010, 10:51:18 am
Post by: Baladya on May 11, 2010, 10:53:27 am
...to the nearest what?
Ya whole number... My question is that we should do it like dividing (upper bound of 1st number - lower bound of 2nd number)
Post by: Ghost Of Highbury on May 11, 2010, 10:55:17 am
If we want to calculate lower and upper bound of lets say 6-4.
For upper bound we minus 6.5 minus 3.5 and for lower bound 5.5 - 4.5?
Thanks
explain clearly plz.
wat is "6-4" do u mean "6.4" ??
wat do u mean by " minus 6.5 minus 3.5"
Post by: Adzel on May 11, 2010, 10:56:24 am
If we want to calculate lower and upper bound of lets say 6-4.
For upper bound we minus 6.5 minus 3.5 and for lower bound 5.5 - 4.5?
Thanks
+ 0.5 to upper bound --> 6.5 - 4.5
- 0.5 to lower bound --> 5.5 - 3.5
Post by: Baladya on May 11, 2010, 10:57:15 am
explain clearly plz.
wat is "6-4" do u mean "6.4" ??
wat do u mean by " minus 6.5 minus 3.5"
K Adzel :D Thanks :P
Aodi, my bad :P
Post by: Adzel on May 11, 2010, 10:58:59 am
attached.
PQS = 80 degree.
Angle PQS = Angle PRS
the chord circumference rule.
QPR = 180 - 80 - 33 = 67 degree. (Angle Sum property)
PSQ => PXS = 147 (180-33). PSX = 180 - 147 - 21 = 12 degree.
Thanks A@di...
Post by: Ghost Of Highbury on May 11, 2010, 10:59:24 am
Post by: Vin on May 11, 2010, 11:00:27 am
multiplication / addition
LB = LB + LB
LB = LB* LB
UB =UB + UB
UB = UB*UB
subtraction/divsion
LB = LB -UB
LB = LB/UB
UB = UB - LB
UB = UB/LB
correct me if im wrong..
Post by: thenewkid™ on May 11, 2010, 11:19:52 am
and
oct/nov 2009 p2 q4 variant 1
pls Thanks
Post by: Adzel on May 11, 2010, 11:21:19 am
may/june 2009 p2 q18 variant 1
and
oct/nov 2009 p2 q4 variant 1
pls Thanks
Ans Q18 (a) 1080 33
------- = -------- = 320 cm3
s 23
(b) s 32
------- = -------- = 567 cm2
252 22
Post by: Ghost Of Highbury on May 11, 2010, 11:27:25 am
may/june 2009 p2 q18 variant 1
and
oct/nov 2009 p2 q4 variant 1
pls Thanks
ans 4) 5x^1.5
----------------
8
-----------------
x^-5/2
-------------------
2
Answer : 1.25x4
Post by: Adzel on May 11, 2010, 01:01:08 pm
Q14 (b)
Q19 (b)
Q22 (b)
+explaination please...thanks
Post by: Vin on May 11, 2010, 01:13:04 pm
Q11 (b)
Q14 (b)
Q19 (b)
Q22 (b)
+explaination please...thanks
gimme 2 mins .. :)
Post by: soualhi1 on May 11, 2010, 01:30:34 pm
Like, when it is B' U A, is it true we do the B' first before the A?
Post by: Adzel on May 11, 2010, 01:39:53 pm
gimme 2 mins .. :)
30 mins past and no reply :(
Post by: Adzel on May 11, 2010, 01:40:34 pm
So we prioritize the first instruction that comes?
Like, when it is B' U A, is it true we do the B' first before the A?
True. ;)
Post by: Fastal on May 11, 2010, 01:59:34 pm
So we prioritize the first instruction that comes?
Like, when it is B' U A, is it true we do the B' first before the A?
isnt A U B' the same as B' U A
Post by: haris94 on May 11, 2010, 02:14:54 pm
Post by: Vin on May 11, 2010, 02:28:54 pm
im not quite sure about Q11 n Q14(b) .. they dont match my answers from the ms.. ??? ???
19 b)
9999 = 104 - 1
theres a rule (a2 - b2) = (a+b) (a-b)
so, (102 + 1) (102 - 1)
now if u notice (102 - 1) also falls under the above rule ..
(102 + 1) ( 10 +1) (10-1)
101 x 11 x 9
they hav asked 'as a product of prime factors.'
so tht would be
101 x 11 x 3 x 3
Q22 (b)
if u see it forms a right angled triangle
OA and AB are 15 each .. thrice p/w
so by Pythagoras ..
OBsup]2[/sup] = 52+52
OB = 21.2
Post by: Fastal on May 11, 2010, 02:38:03 pm
x=230 and 310.
continue the sine curve on theleft side of the graph they gave. this tells you that the curve from 0 to -180 is the same as from 360 to 180
thus 360-50
and 180+50
11b-dont really understand
Post by: Adzel on May 11, 2010, 02:42:15 pm
14b
x=230 and 310.
continue the sine curve on theleft side of the graph they gave. this tells you that the curve from 0 to -180 is the same as from 360 to 180
thus 360-50
and 180+50
11b-dont really understand
I did the same thing but the mark shcheme said its wrong...???
Post by: Adzel on May 11, 2010, 02:45:07 pm
OA and AB are 15 each .. thrice p/w
I did not understand this part... :-\
Post by: Vin on May 11, 2010, 02:47:17 pm
Post by: Vin on May 11, 2010, 02:50:08 pm
I did not understand this part... :-\
If u see OA is actually 3 times p tht is
OA =OP + PQ + QA
OA = 5+5+5
=15
n same for AB
AB= AR+RS+SB
= 5+5+5
=15
..
Post by: Fastal on May 11, 2010, 02:51:07 pm
I did the same thing but the mark shcheme said its wrong...???
can you post the marking scheme, i cant find it
Post by: haris94 on May 11, 2010, 02:55:26 pm
£1 = 15.2978 Chinese Yuan.
Calculate the amount he received, giving your answer correct to 2 decimal places.
(b) In 2006, the exchange rate was £1 = 15.9128 Chinese Yuan.
Calculate the percentage decrease in the number of Chinese Yuan for each £1 from
2006 to 2007.
someone tell me how to do "b" part and please explain
Thanks
Post by: astarmathsandphysics on May 11, 2010, 02:56:53 pm
Post by: astarmathsandphysics on May 11, 2010, 02:59:07 pm
(new-original)/original*100%
Post by: Fastal on May 11, 2010, 03:00:18 pm
17 (a) In 2007, a tourist changed 4000 Chinese Yuan into pounds (£) when the exchange rate was
£1 = 15.2978 Chinese Yuan.
Calculate the amount he received, giving your answer correct to 2 decimal places.
(b) In 2006, the exchange rate was £1 = 15.9128 Chinese Yuan.
Calculate the percentage decrease in the number of Chinese Yuan for each £1 from
2006 to 2007.
someone tell me how to do "b" part and please explain
Thanks
percentage decrease=old value-newvalue/oldvalue*100
so here
%=0.615/15.9128*100
thus % decrease=3.86%
Post by: Adzel on May 11, 2010, 03:00:46 pm
so by Pythagoras ..
OB = 52+52
= 21.2
And you wrote this >:(
Post by: Adzel on May 11, 2010, 03:02:34 pm
can you post the marking scheme, i cant find it
Here you go..see it by your self :-\
Post by: Malak on May 11, 2010, 03:03:19 pm
Q: 20 part b
thx
Post by: haris94 on May 11, 2010, 03:10:22 pm
(15.9128-15.2978)/15.2978*100
(new-original)/original*100%
i tried that but the ms says
(15.9128-15.2978)/15.9128*100 ??? ???
Post by: haris94 on May 11, 2010, 03:15:54 pm
percentage decrease=old value-newvalue/oldvalue*100
so here
%=0.615/15.9128*100
thus % decrease=3.86%
u r saying percentage decrease=old value-newvalue/oldvalue*100
the old value is 15.2978
so shouldnt it be
(15.9128-15.2978)/15.2978*100
the ms answer is the same as yours
but the formula disagrees with the answer
Post by: astarmathsandphysics on May 11, 2010, 03:16:50 pm
alwys divide by original
Post by: haris94 on May 11, 2010, 03:24:26 pm
Post by: Malak on May 11, 2010, 03:26:03 pm
Q9 And Q15 part b and c http://www.freeexampapers.us/IGCSE/Maths/CIE/2007%20Nov/0580_w07_qp_2.pdf (http://www.freeexampapers.us/IGCSE/Maths/CIE/2007%20Nov/0580_w07_qp_2.pdf)
Thx
Post by: Adzel on May 11, 2010, 03:29:44 pm
Post by: PeaceMaker on May 11, 2010, 03:32:45 pm
this one please..
I would love to know part (a) these questions always come and i always get confuse by them so, anyone care to explain?
Post by: Vin on May 11, 2010, 03:36:41 pm
once u kno the area beneath 8-10 which is 19.4
A (trapezium) = 1/2 * ( sum of parallel sides ) * h
so 19.4 = 1/2 ( x + 12.4 ) * 2
19.4 = x + 12.4
x = 19.4 - 12.4
x= 7
Post by: Adzel on May 11, 2010, 03:38:51 pm
I would love to know part (a) these questions always come and i always get confuse by them so, anyone care to explain?
Easy...just find the upper bound and the lower bound, as it said to the nearest km i.e. 1/2 = 0.5
So, 22 - 0.5 = 21.5 (lower bound)
22 + 0.5 = 22.5 (upper bound)
i.e. 21.5 < d < 22.5
....but im only concerned about part (b)
Post by: Malak on May 11, 2010, 03:42:09 pm
Easy...just find the upper bound and the lower bound, as it said to the nearest km i.e. 1/2 = 0.5
So, 22 - 0.5 = 21.5 (lower bound)
22 + 0.5 = 22.5 (upper bound)
i.e. 21.5 < d < 22.5
....but im only concerned about part (b)
Its least amount...so just multiply ur lower bound with 5 to get the distance for 5 days n thn multiply with the amount of money...
Post by: haris94 on May 11, 2010, 03:44:22 pm
lower bound=22-0.5 = 21.5km
1 day he walks 21.5km
5 days = 21.5*5 = 107.5km
1 km = $1.6
107.5km = 1.6*107.5 = $172
Post by: Adzel on May 11, 2010, 03:44:49 pm
Q 20)
once u kno the area beneath 8-10 which is 19.4
A (trapezium) = 1/2 * ( sum of parallel sides ) * h
so 19.4 = 1/2 ( x + 12.4 ) * 2
19.4 = x + 12.4
x = 19.4 - 12.4
x= 7
how did you get 19.4???
Post by: diva_sparkles on May 11, 2010, 03:46:10 pm
u r saying percentage decrease=old value-newvalue/oldvalue*100
the old value is 15.2978
so shouldnt it be
(15.9128-15.2978)/15.2978*100
the ms answer is the same as yours
but the formula disagrees with the answer
it shld be (15.9128-15.2978)/15.2978*100 cos it it says in 2006 it wz 15.9128 n in 2007 it wz 15.2978 so ms is rite!!! :)
Post by: Adzel on May 11, 2010, 03:46:25 pm
Post by: haris94 on May 11, 2010, 03:46:36 pm
how did you get 19.4???
total distance - distance in first 8s
so
100m-80.6
=19.4m
Post by: haris94 on May 11, 2010, 03:48:12 pm
it shld be (15.9128-15.2978)/15.2978*100 cos it it says in 2006 it wz 15.9128 n in 2007 it wz 15.2978 so ms is rite!!! :)
o yea sorry mixed 'em up :-[
Thanks
Post by: Malak on May 11, 2010, 03:48:35 pm
Q9 And Q15 part b and c http://www.freeexampapers.us/IGCSE/Maths/CIE/2007%20Nov/0580_w07_qp_2.pdf (http://www.freeexampapers.us/IGCSE/Maths/CIE/2007%20Nov/0580_w07_qp_2.pdf)
Post by: Dark Prince on May 11, 2010, 03:53:21 pm
Post by: princess12 on May 11, 2010, 03:56:06 pm
Post by: Ghost Of Highbury on May 11, 2010, 04:01:49 pm
can someone tell me the difference between mutally exclusive nd non-mutally exclusive in probability......with examples....i m difficulty in probability nd in the OR rule specially the erms mentioned above.....thnkx...plzzz its urgent
i can explain better if u provide me with a q..
Post by: xMilishax on May 11, 2010, 04:05:59 pm
Anyone...?
Q9 And Q15 part b and c http://www.freeexampapers.us/IGCSE/Maths/CIE/2007%20Nov/0580_w07_qp_2.pdf (http://www.freeexampapers.us/IGCSE/Maths/CIE/2007%20Nov/0580_w07_qp_2.pdf)
9) p = 2, q = -12
15b) 1/2a + 1/3b 15c) -1/2a +1/6b
Post by: Malak on May 11, 2010, 04:07:13 pm
9) p = 2, q = -12
15b) 1/2a + 1/3b 15c) -1/2a +1/6b
umm.....Well....Can u kinda explain...?thx
Post by: Alpha on May 11, 2010, 04:07:30 pm
can someone tell me the difference between mutally exclusive nd non-mutally exclusive in probability......with examples....i m difficulty in probability nd in the OR rule specially the erms mentioned above.....thnkx...plzzz its urgent
Mutually exclusive> events that are mutually INDEPENDENT of the occurrence of the other.
E.g. 1)
> From a group of six coloured balls, pick up a ball, note its colour. Replace the ball. Pick up another ball, then note the colour.
Mutually non-exclusive > events that are dependent on each other.
E.g. 2)
> From a group of six coloured balls, pick up a ball, note its colour. Pick up another ball, then note the colour.
In the 2nd example, you don't replace the ball you had first picked up. So, after the first action, there remains only 5 balls to be chosen from, i. e. the 2nd probability in 2nd example will be 1/5, instead of 1/6 as in the 1st example.
AND Multiply the probabilities. And is for "both". Both events should occur.
OR Add the probabilities. Or is for "either or", that is one of the two events.
Post by: Ghost Of Highbury on May 11, 2010, 04:08:31 pm
Anyone...?
Q9 And Q15 part b and c http://www.freeexampapers.us/IGCSE/Maths/CIE/2007%20Nov/0580_w07_qp_2.pdf (http://www.freeexampapers.us/IGCSE/Maths/CIE/2007%20Nov/0580_w07_qp_2.pdf)
ans 9) (x+2)2 = x2 + 4x + 4.
x2 + 4x + 4 -12 = x2 + 4x - 8
thus, (x+2)2 - 12
Post by: Ghost Of Highbury on May 11, 2010, 04:22:28 pm
To reach E from O. u have to go 3 lines towards A and 2 towards B
= 3*a/6 + 2*b/6 = a/2 + b/3
15c) EB is EO + OB
EO = -(OE) = -(a/2+b/3) = -a/2 - b/3
OB = b
hence => EB = -a/2 - b/3 + b = -a/2 + b/6
Post by: haris94 on May 11, 2010, 04:25:52 pm
ans 9) (x+2)2 = x2 + 4x + 4.
x2 + 4x + 4 -12 = x2 + 4x - 8
thus, (x+2)2 - 12
Thanks
i got it atlast
Post by: haris94 on May 11, 2010, 04:28:45 pm
(a) Calculate f(0.5).
(b) Write down the value of f -1(1).
i dont get the "b" part
how do u find the inverse of 10x ???
Post by: Ghost Of Highbury on May 11, 2010, 04:44:32 pm
7 f(x) = 10x.
(a) Calculate f(0.5).
(b) Write down the value of f -1(1).
i dont get the "b" part
how do u find the inverse of 10x ???
y = 10x
x = 10^y
log x = y
f(-1) x = log x
f^(-1) 1 = log 1 = 0
longer method..
which paper is this from?
Post by: Ghost Of Highbury on May 11, 2010, 04:47:16 pm
f-1(1) means, for what value of x in 10x will u get 1
answer = 0
for e.g f(x) = x+2
f-1x = x-2
f(2) = 4
put 4 in f-1x and u shud get 2
4 -2 = 2
see?
simple.
Post by: ksitna on May 11, 2010, 05:04:16 pm
Post by: Mr.DitD on May 11, 2010, 05:08:21 pm
I had a confusion about the decimal points. When exactly do we have to put decimal point and we do we have to write whole number?!?! ???
Post by: haris94 on May 11, 2010, 05:09:10 pm
y = 10x
x = 10^y
log x = y
f(-1) x = log x
f^(-1) 1 = log 1 = 0
longer method..
which paper is this from?
this is from O/N 2005
Post by: Ghost Of Highbury on May 11, 2010, 05:13:33 pm
this is from O/N 2005
check d easier method i posted
Post by: haris94 on May 11, 2010, 05:14:37 pm
if u havent learnt log. try this method
f-1(1) means, for what value of x in 10x will u get 1
answer = 0
for e.g f(x) = x+2
f-1x = x-2
f(2) = 4
put 4 in f-1x and u shud get 2
4 -2 = 2
see?
simple.
o i c
yea this is much simpler
havent learnt log
this is the first question of its kind i hv seen though
Thanks a lot
Post by: Dibss on May 11, 2010, 05:18:25 pm
Quote
Hello everyone!!
I had a confusion about the decimal points. When exactly do we have to put decimal point and we do we have to write whole number?!?! Huh?
if the number is not exact (i.e. it continues after a decimal until the end of your calculator display) you have to give the answer to three significant figures.
write a whole no. only if they specify or if the answer is exact e.g. 517
if the answer is in degrees, give the answer to one decimal place
:]
Post by: ksitna on May 11, 2010, 05:19:53 pm
Hello everyone!!
I had a confusion about the decimal points. When exactly do we have to put decimal point and we do we have to write whole number?!?! ???
u mean like significant figures?
or standard form?
if u meant the answer in the exam
basically write the answers to 2 decimal places
Post by: $H00t!N& $t@r on May 11, 2010, 05:21:09 pm
if u havent learnt log. try this methodCan you plz give me some more examples on such kind of ques.
f-1(1) means, for what value of x in 10x will u get 1
answer = 0
for e.g f(x) = x+2
f-1x = x-2
f(2) = 4
put 4 in f-1x and u shud get 2
4 -2 = 2
see?
simple.
Post by: holtadit on May 11, 2010, 05:24:37 pm
AND
that some parallelograms can be rectangles or soemthing along those lines.
Can someone please please explain this..
Post by: Ghost Of Highbury on May 11, 2010, 05:27:12 pm
Can you plz give me some more examples on such kind of ques.
check the attached image.
f(x) and f-1(x) is given
u put any values of f-1(x) and calculate u shud get the corresponding value of f(X)
its called one to one function
Post by: Dibss on May 11, 2010, 05:29:23 pm
http://www.algebra.com/algebra/homework/Rectangles/Different-between-parallelogram-rectangle-square-rhombus-and-trapezoid.lesson
http://regentsprep.org/Regents/math/geometry/GP9/LRectangle.htm
Post by: thenewkid™ on May 11, 2010, 05:31:12 pm
Post by: Mr.DitD on May 11, 2010, 05:32:39 pm
Cuz sometimes u need to use the previous value for getting the next answer and ur answer will be different when you use 3.56 instead of 3.6 or 3!
Post by: Ghost Of Highbury on May 11, 2010, 05:33:17 pm
I remember our teacher giving a horrible explanation about how all rhombuses are squares bla blah
AND
that some parallelograms can be rectangles or soemthing along those lines.
Can someone please please explain this..
ANy 4 sided figure is called a quadrilateral.
A quadrilateral with opposite sides are parallel and equal in length, and opposite angles equal is called a parallelogram
A parallelogram with 4 right angles and and with congruent diagonals is called a rectangle.
A rhombus is a four-sided shape where all sides have equal length.
Also opposite sides are parallel and opposite angles are equal.
The diagonals of a rhombus bisect each other at right angles.
Post by: Fastal on May 11, 2010, 05:35:04 pm
ANy 4 sided figure is called a quadrilateral.
A quadrilateral with opposite sides are parallel and equal in length, and opposite angles equal is called a parallelogram
A parallelogram with 4 right angles and and with congruent diagonals is called a rectangle.
A rhombus is a four-sided shape where all sides have equal length.
Also opposite sides are parallel and opposite angles are equal.
The diagonals of a rhombus bisect each other at right angles. (thats wat makes it different from a square)
but a square is a rhombus
Post by: haris94 on May 11, 2010, 05:39:18 pm
and can u tell me what is a plane symmetry
and if u hv seen any other questions with plane symmetry in the past papers pls tell me
Thank You
Post by: Ghost Of Highbury on May 11, 2010, 05:39:31 pm
congruent (equal) sides. But there are rhombuses that are not square,
because their angles are not right angles.
Post by: Baladya on May 11, 2010, 05:44:41 pm
question 21 b) pleaseA plane of symmetry is like the line of symmetry but for 3D shapes (i.e a cube)
and can u tell me what is a plane symmetry
and if u hv seen any other questions with plane symmetry in the past papers pls tell me
Thank You
http://www.m-a.org.uk/cabri/issue-02/files/cube-symmetry-one.jpg (http://www.m-a.org.uk/cabri/issue-02/files/cube-symmetry-one.jpg)
So it just cuts it into two IDENTICAL halves
Post by: haris94 on May 11, 2010, 05:48:40 pm
A plane of symmetry is like the line of symmetry but for 3D shapes (i.e a cube)
http://www.m-a.org.uk/cabri/issue-02/files/cube-symmetry-one.jpg (http://www.m-a.org.uk/cabri/issue-02/files/cube-symmetry-one.jpg)
So it just cuts it into two IDENTICAL halves
ok Thanks
im surprised i never knew that :o
Post by: diva_sparkles on May 11, 2010, 06:01:49 pm
Post by: Fastal on May 11, 2010, 06:02:56 pm
22c
i know the answer is probably staring at me in the face, but please tell me :/
Post by: The Hitman on May 11, 2010, 06:04:59 pm
i keep forgetting it...
Post by: ksitna on May 11, 2010, 06:08:13 pm
umm, guys... can someone tell me the formula for quadratic equations?
i keep forgetting it...
-b+-square root b squared-4ac
over 2a
Post by: Adzel on May 11, 2010, 06:09:03 pm
[-b +or- sqaure root (b2-4ac)]/2a
Post by: holtadit on May 11, 2010, 06:09:50 pm
umm, guys... can someone tell me the formula for quadratic equations?
i keep forgetting it...
There's something called Google.com :)
Post by: Adzel on May 11, 2010, 06:11:25 pm
2009 may/june
22c
i know the answer is probably staring at me in the face, but please tell me :/
58
Post by: haris94 on May 11, 2010, 06:14:03 pm
There's something called Google.com :)
lol
google.....the all knowing :P
Post by: Adzel on May 11, 2010, 06:17:39 pm
- Exept currency/money round it to two decimal points. e.g. your answer is $545.756 ----> $545.76
Post by: haris94 on May 11, 2010, 06:17:48 pm
well actualy my teacher tht ths isnt in da syllabus!! n da examiners gav a mark 4 all da candidates as ths wasn in da syllabus!! :)
wow!!
now im hoping tomorrow v get a question out of the syllabus :P
Post by: ksitna on May 11, 2010, 06:20:09 pm
@ ksitna: - Round your answer to three segnificant figiurs. e.g. your answer is 0.2356 ----> 0.236
- Exept currency/money round it to two decimal points. e.g. your answer is $545.756 ----> $545.76
yup thx
and degrees to 1 decimal place:)
Post by: Shazizzzle on May 11, 2010, 06:20:22 pm
@ ksitna: - Round your answer to three segnificant figiurs. e.g. your answer is 0.2356 ----> 0.236
- Exept currency/money round it to two decimal points. e.g. your answer is $545.756 ----> $545.76
And answers to angles, in degrees, to ONE decimal place, if not specified in the question itself. :)
Post by: Fastal on May 11, 2010, 06:20:34 pm
58
can you tell me why please??
Post by: Malak on May 11, 2010, 06:21:59 pm
Thx alot
Post by: Shazizzzle on May 11, 2010, 06:24:07 pm
can you tell me why please??
DCA = DAT (Alternate Segment Theory)
If DAO = 32, DAT = 90 - 32 = 58.
So, DCA = 58. :)
Post by: Dibss on May 11, 2010, 06:25:57 pm
Quote
58
can you tell me why please??
hey, I'm assuming you know the alternate segment theorem which says the angle between a tangent and a chord drawn form the point of contact is equal to any angle in the alternate segment.
in your qs, DAT will be equal to any angle subtended by line AD in the opposite segment. therefore angle DAT=ACD=58 :]
Post by: Shazizzzle on May 11, 2010, 06:28:17 pm
Nov 09 Q 4 & 14 http://www.freeexampapers.us/IGCSE/Maths/CIE/2009%20Nov/0580_w09_qp_22.pdf (http://www.freeexampapers.us/IGCSE/Maths/CIE/2009%20Nov/0580_w09_qp_22.pdf)
Thx alot
Umm, separate the coeffecients from the variables.
i.e First do 5/8 / 1/2
=5/8 X 2/1 (reciprocal of 1/2 taken when introducing multiplication)
=10/8
1/1/4.
Then the variables.
x^3/2 / x^-5/2
=x^ 3/2 - (-5/2)
=x^3/2+5/2
=x^8/2
=x^4
So, Answer: 1/1/4x^4 :)
Post by: Dark Prince on May 11, 2010, 06:29:19 pm
its vertically left.
Sorry to ask this again......but i still dont get it hoe is it moving to left...thnkx
Post by: Fastal on May 11, 2010, 06:30:16 pm
hey, I'm assuming you know the alternate segment theorem which says the angle between a tangent and a chord drawn form the point of contact is equal to any segment in the alternate segment.
in your qs, DAT will be equal to any angle subtended by line AD in the opposite segment. therefore angle DAT=ACD=58 :]
Thank You
+rep
Post by: Dibss on May 11, 2010, 06:32:39 pm
Quote
Nov 09 Q 4 & 14 http://www.freeexampapers.us/IGCSE/Maths/CIE/2009%20Nov/0580_w09_qp_22.pdf14:
Thx alot
P(1+R/100)^T
249(1+1.7/100)3
=261.92
Interest =261.92-249 =12.92
Fastal, you're welcome :]
Post by: Fastal on May 11, 2010, 06:33:34 pm
Sorry to ask this again......but i still dont get it hoe is it moving to left...thnkx
i dont get it either :(
Post by: haris94 on May 11, 2010, 06:35:07 pm
Nov 09 Q 4 & 14 http://www.freeexampapers.us/IGCSE/Maths/CIE/2009%20Nov/0580_w09_qp_22.pdf (http://www.freeexampapers.us/IGCSE/Maths/CIE/2009%20Nov/0580_w09_qp_22.pdf)
Thx alot
Q 4) whenever it is division, u hv to subtract the powers
so 3/2 - (-5/2) = 4
and (5/8)/(1/2) is equal to 5/4 or 1.25
so answer is 1.25x4
Post by: haris94 on May 11, 2010, 06:39:27 pm
Nov 09 Q 4 & 14 http://www.freeexampapers.us/IGCSE/Maths/CIE/2009%20Nov/0580_w09_qp_22.pdf (http://www.freeexampapers.us/IGCSE/Maths/CIE/2009%20Nov/0580_w09_qp_22.pdf)
Thx alot
Q 14)
A = P(1+r/100)n
A = 249(1+1.7/100)3
A = $261.92
interest = A-P
261.92-249
$12.92
Post by: haris94 on May 11, 2010, 06:46:01 pm
i dont get it either :(
from the x-axis u need to move -1 to reach the triangle
this is what i think
if from the x-axis u need to move left, then factor is in -ve
if u move right, factor will be a +ve number
Post by: 33oomar on May 11, 2010, 06:53:01 pm
Post by: Shazizzzle on May 11, 2010, 06:54:16 pm
from the x-axis u need to move -1 to reach the triangle
this is what i think
if from the x-axis u need to move left, then factor is in -ve
if u move right, factor will be a +ve number
This is all crap.
It's clear that if y-axis is the invariant line, up (right, if y-axis is brought horizontal) is +ve, down is negative.
If the x-axis is the invariant line, right is positive and left negative.
People say it's related to the quadrant the shear was in.
The only explanation is that CIE made a mistake and was too lame to admit it, even in the ER, therefore defended the answers WITHOUT GIVING A CLEAR EXPLANATION TO WHY IT WAS -ve.
Also, the principal examiner, has expressed how he would like to reduce graph and transformation questions as they are easy, and replace them with difficult investigating, sequence and probability questions.
As transformation showed up in Nov 2009, is it unlikely to show up this year.
Also, that question was from Paper 4.
We've got Paper 2 tomorrow. Chillax. :)
Post by: The Hitman on May 11, 2010, 06:56:52 pm
There's something called Google.com :)...
...
...
LMAO!
*sings google is your friend*
Post by: Shazizzzle on May 11, 2010, 06:57:49 pm
what is the rule for compound intrest please no symbols full words
The principal amount is the one you invest.
The formula for compound interest, P(1+r/100)^t, is when, P is principal amount, r, the rate, and t, the time.
If the rate is yearly, then the time, t, must too be in years.
If the rate is monthly, the time, t, must be monthly too.
The answer you get to the formula above IS NOT THE INTEREST. It is the TOTAL AMOUNT.
If you invest 200, and the answer you get to the formula is 300, the 300 is not the interest, rather the TOTAL you get.
The interest is, total - principal, 300 - 200 = 100.
Post by: rahuldevnani93 on May 11, 2010, 06:59:13 pm
Please
Email to :- rahul_gurukul@yahoo.com
Post by: Vin on May 11, 2010, 07:04:50 pm
2009 may/june
22c
i know the answer is probably staring at me in the face, but please tell me :/
sorry its a bit untidy .. i think its a lot untidy .. :)
Post by: The Golden Girl =D on May 11, 2010, 07:08:20 pm
Guys I need the markscheme for the old paper 1988 - 1995
Please
Email to :- rahul_gurukul@yahoo.com
it's in this website jut so u know ..ohh but not the whole thing ::)
Post by: Baladya on May 11, 2010, 07:11:39 pm
2)iv) I know its a shear, i know the invariant line is the y-axis, i thought the shear factor was 1 (4/4=1). But the answer says -1. Why???? >.< >.<
By the way.. for probability, we can simplify the fraction right? cuz the calculator just gives u the simplest form and its easier...
Post by: ivrytwr3 on May 11, 2010, 07:18:53 pm
Write down the gradient of the line y=3x-4
and then:
Write down the equation of a line through (0,0) parallel to y=3x-4
thanks!
Post by: Dibss on May 11, 2010, 07:21:00 pm
Quote
for probability, we can simplify the fraction right? cuz the calculator just gives u the simplest form and its easier...yep, it's actually better if you simplify!
Post by: Ghost Of Highbury on May 11, 2010, 07:24:50 pm
Can someone explain how you do this one? (i know it's meant to be easy, but i haven't looked at how to do these :()
Write down the gradient of the line y=3x-4
and then:
Write down the equation of a line through (0,0) parallel to y=3x-4
thanks!
y = mx + x
m = gradient
y = 3x-4
m = 3 = gradient.
parallel to y=3x-4 means that it has the same gradient = 3
y = 3x+c
wen x = 0, y = 0 (0,0)
0 = 3*0 + c
0 = 0 + c
c = 0
y = 3x
Post by: 33oomar on May 11, 2010, 07:28:27 pm
The principal amount is the one you invest.
The formula for compound interest, P(1+r/100)^t, is when, P is principal amount, r, the rate, and t, the time.
If the rate is yearly, then the time, t, must too be in years.
If the rate is monthly, the time, t, must be monthly too.
The answer you get to the formula above IS NOT THE INTEREST. It is the TOTAL AMOUNT.
If you invest 200, and the answer you get to the formula is 300, the 300 is not the interest, rather the TOTAL you get.
The interest is, total - principal, 300 - 200 = 100.
Thanks alot dude you really saved my A** ;D
Post by: Adzel on May 11, 2010, 07:38:22 pm
Post by: Shazizzzle on May 11, 2010, 07:38:30 pm
But, they say the obtuse angle.
So, does that mean the larger PQR?
That would be 360 - 54.0.
OR, do they mean obtuse, as in, using the Quadrant II law, 180 - x = 180 -54.0?
Post by: Ghost Of Highbury on May 11, 2010, 07:40:38 pm
Post by: Shazizzzle on May 11, 2010, 07:41:48 pm
Is there any transformation, hitogram and line grahs in paper2 ???
Yes. All three.
Transformation, usually relating to smaller Qs. i.e reflection and rotation etc.
They just ask you to identify the transformation and the matrix.
Line graphs, yes... For calculating gradients. And in linear programming to find a required region by shading.
Histogram, indeed there is, when half is drawn, the other half you have to complete, and usually complete a table.
Post by: Vin on May 11, 2010, 07:45:58 pm
I hate HISTOGRAMS .. !! somebody any tip for solving them ?? u wan me to post a paper ?? pls anything.. :)
Post by: Adzel on May 11, 2010, 07:46:52 pm
Yes. All three.
Transformation, usually relating to smaller Qs. i.e reflection and rotation etc.
They just ask you to identify the transformation and the matrix.
Line graphs, yes... For calculating gradients. And in linear programming to find a required region by shading.
Histogram, indeed there is, when half is drawn, the other half you have to complete, and usually complete a table.
Do you remember which past papers contain them ???...me too ::)
Post by: Vin on May 11, 2010, 07:49:39 pm
like this one .. =|
Post by: Shazizzzle on May 11, 2010, 07:50:44 pm
I hate HISTOGRAMS .. !! somebody any tip for solving them ?? u wan me to post a paper ?? pls anything.. :)
f.d = k X f/c.w
K, the constant.
When, both frequency AND histogram i.e frequency density for one group are given, use them to find K.
Sometimes, the f.d may not be equal to f/c.w.
Once you have, use the formula to either find
1. f.d of groups with F already given, and use it to make the bar...
OR
2. Use the f.d on the histogram given to find th F and record in table. :)
Post by: Ghost Of Highbury on May 11, 2010, 07:53:21 pm
ok this negative shear factor thingy is horrible..i cant figure it out y the move upwards is considered negative.
anyhow, its always wiser to use the matrix method
take two object and correspoding image co-ordinates..
(-4,1) --> (-4,5)
(-1,1) --> (-1,2)
check the image attached
a shear transformation matrix with y-axis is invariant is = (1 0)
(k 1)
here k = -1
Post by: Adzel on May 11, 2010, 07:55:00 pm
f.d = k X f/c.w
K, the constant.
When, both frequency AND histogram i.e frequency density for one group are given, use them to find K.
Sometimes, the f.d may not be equal to f/c.w.
Once you have, use the formula to either find
1. f.d of groups with F already given, and use it to make the bar...
OR
2. Use the f.d on the histogram given to find th F and record in table. :)
Can you explain more; like what is k and c.w ???
Post by: ksitna on May 11, 2010, 07:59:12 pm
i just realised we usually have the same number of posts :)
Post by: Baladya on May 11, 2010, 07:59:38 pm
If u have a group of data in a table annd u want to find the median, here is the way.
If the total number of data (cumulative frequency) is an even number do this: Calculate n/2. Calculate (n/2)+2. Get the average of them. The average tells the postition of the median(undeer which group).
If its an odd number: Don't remember xD ;D Anyone knows :P???
Hope this helped...
Post by: Baladya on May 11, 2010, 08:00:19 pm
loll hey baladya
i just realised we usually have the same number of posts :)
NOOO U CHEATED xD ;D Hahaha Weird :D
Post by: Ghost Of Highbury on May 11, 2010, 08:01:01 pm
like this one .. =|
can u give the answers too plz? maybe i can help..
Post by: Shazizzzle on May 11, 2010, 08:05:04 pm
like this one .. =|
Here, for e.g., 0-10 has 300 patients.
f.d=15 (count squares height)
frequency=300 (given in table)
c.w (class width)= 10 (0-10, the interval width is 10)
f.d = k X f/c.w
15 = K X 300/10
15=K x 30
K=15/30
K=1/2
Now, the area of the bar is 5 X 15 = 75
Frequency is 300
So, frequency for one small block: 300/75 = 4
and, the number of small blocks in 1 cm^2 = 25 (5 X 5)
SO, frequency of 1cm^2= 4 X 25 = 100 patients.
Now, part b.
The height, of f.d is 20.
We need F (i.e no of patients to fill table)
f.d = k X f/cw
20 = 1/2 X f/30
20 = f/60
f= 20 X 60
f=1200
Post by: Vin on May 11, 2010, 08:05:55 pm
Post by: Shazizzzle on May 11, 2010, 08:08:13 pm
Total number of terms (sum of frequencies) = n
n/2
if the ans to the above is in decimals, e.g say 7.5, the you round it, to the next term. 8. So THE 8TH term is THE MEDIAN.
If the ans to the above is an integer, say 10, you take 10, AND THE NEXT, i.e 10th AND 11th terms, take their average (i.e 10th + 11th / 2)
and, voila, that's the median.
SIMPLE. :)
Post by: Vin on May 11, 2010, 08:09:51 pm
u've answered a couple ov answers before too .. Thanks .. :)
Post by: Baladya on May 11, 2010, 08:13:59 pm
Page 6 q. 13 .. post a q. A@di is always there to ans it !! :P Thanks ..
Vin: a) is 20 its because if u take the square next to the origin (1cm3 square) it has a base of 10 years and a hieght of 10 pateints. Just multiply the two as if u want the area of that square
Post by: Shazizzzle on May 11, 2010, 08:15:35 pm
Post by: Ghost Of Highbury on May 11, 2010, 08:15:56 pm
v use the same formula
first find the standard width (k)
sw = (h*cw)/f
then find the height
h = f * (sw/cw)
@baladaya - a is 100. 300/75 = 4. 25*4 = 100
Post by: Shazizzzle on May 11, 2010, 08:19:46 pm
ok shazzizle has already answered.
v use the same formula
first find the standard width (k)
sw = (h*cw)/f
then find the height
h = f * (sw/cw)
@baladaya - a is 100. 300/75 = 4. 25*4 = 100
YES! A=100.
I SECOND THAT! :)
Post by: Vin on May 11, 2010, 08:23:13 pm
this is it i guess .. pls. check i think its wrong .. :\ dunno . . =\
Post by: Ghost Of Highbury on May 11, 2010, 08:25:52 pm
Umm, June 2007, Q12. Which region is shaded?
here
Post by: Vin on May 11, 2010, 08:27:10 pm
i think this is the answer. some1 plz check
Even i got the same .. excepting urs is neater .. ;)
Post by: Shazizzzle on May 11, 2010, 08:30:00 pm
I just got confused with y=5x.
The requires region should be where the y values are greater.
I always thought greater meant further. so y>5x would be FORWARD to the line.
As in, R would be that triangle in the middle.
However I correct myself, and thought the ans I got was weird.
You guys justified it. :)
Post by: ruruiw 60984 on May 11, 2010, 08:30:19 pm
its making me lose my mind..
Thanks in advance
Post by: Baladya on May 11, 2010, 08:32:41 pm
Don't worry, m gonna see lots of these mistakes tommorow (hope not :-X)
Post by: 6394 on May 11, 2010, 08:35:29 pm
Post by: Baladya on May 11, 2010, 08:37:18 pm
formula 4 compound interest ???????????
Original amount (1+rate in decimals)^n
n=number of years
Post by: Adzel on May 11, 2010, 08:37:47 pm
Post by: ruruiw 60984 on May 11, 2010, 08:39:08 pm
Help in Q23 . JUne 2006 P2 > plz
its making me lose my mind..
Thanks in advance
Post by: 6394 on May 11, 2010, 08:40:42 pm
HELP PLEAZZZZZZZZ
???????????????
Post by: Shazizzzle on May 11, 2010, 08:40:43 pm
Help in Q23 . JUne 2006 P2 > plz
its making me lose my mind..
Thanks in advance
Umm, reproduce vectors a and b, in different positions, though they must be parallel, of the same magnitude.
Post by: 6394 on May 11, 2010, 08:42:05 pm
Post by: Vin on May 11, 2010, 08:44:18 pm
No this is the correct shading;
can u pls explain.. ???
@ruruiw im tryin .. a bit tricky tho .. :-\
Post by: Baladya on May 11, 2010, 08:47:05 pm
And make sure its on Mode=comp and SHIFT MODE=Deg
GL ALL :)
Post by: Adzel on May 11, 2010, 08:53:44 pm
y is > greater than or equal to 3
x + y is < less than or equal to 6
Post by: 6394 on May 11, 2010, 08:55:43 pm
4 compond interst
Post by: Shazizzzle on May 11, 2010, 08:56:42 pm
Therefore, the required region is where Y values are greater. And, using the y axis, and the line y=5x, which region has the greater ones?
The one ON TOP.
Greater means greater values.
Not greater, as in, it will be AHEAD.
Post by: Adzel on May 11, 2010, 09:03:35 pm
Yeah, it say Y is greater than and equal to 5x.
Therefore, the required region is where Y values are greater. And, using the y axis, and the line y=5x, which region has the greater ones?
The one ON TOP.
Greater means greater values.
Not greater, as in, it will be AHEAD.
If so then ... im wrong.
Post by: Ghost Of Highbury on May 11, 2010, 09:06:48 pm
check the attached image
ai) VW = VU + UX + XW = -a + b + 2a = a+b
aii) TU = TX + XU = a-b
aiii) TP = TW + WP = 3a+b
aiv) OP = OZ + ZP = 1.5a + 0.5b
b = a-b = TU = 4 units
Post by: 6394 on May 11, 2010, 09:08:01 pm
Post by: Vin on May 11, 2010, 09:09:29 pm
Help in Q23 . JUne 2006 P2 > plz
its making me lose my mind..
Thanks in advance
23 a) VW = a + b
simply because VW is in the same direction as a and b
ii)TU = a - b
TU in the same direction as 'a' but opp. to 'b'
iii) is attached .. its a bit complicated ..
wonder how i got UA as 'b'
VA is clearly b-a
so 'UA' + AV should be equal to "a"
so UV = UA + AV
a = UA + a - b
so UA = b
same stuff for BP WB also which gives us a
so adding UA , AB , BP and TU u get TP
=b + (a +b) + a
= 3a +b
gosh pls. dont freal out if u dont understand .. i did my best to explain ..
iv) from origin position ov p is 1/2 TP
= 1.5a + 1/2 b
v) is simply count no. of blocks of TU = 4
Post by: saleemsamer on May 11, 2010, 09:10:25 pm
Post by: Vin on May 11, 2010, 09:11:13 pm
Post by: Vin on May 11, 2010, 09:15:31 pm
m/j 07 p2 q20 plz
a) bisector of A B
b) 3 cm radius circle
c) measure at point when exactly at circumference of D
Post by: 6394 on May 11, 2010, 09:17:51 pm
Post by: Ghost Of Highbury on May 11, 2010, 09:19:17 pm
@Vin - No problem man, its alright. Good luck for the exam, and go sleep, u need it.
Post by: 6394 on May 11, 2010, 09:21:09 pm
??? ???
Post by: Adzel on May 11, 2010, 09:22:11 pm
m/j 07 p2 q20 plz
Here ya' go;
Post by: Shazizzzle on May 11, 2010, 09:23:53 pm
Oct/Nov 2008, Paper 21, Q5. :)
Post by: Vin on May 11, 2010, 09:26:22 pm
Signing Off now. Its almost 2 am here. Best of luck to all of you. Do well! Night guyz.
@Vin - No problem man, its alright. Good luck for the exam, and go sleep, u need it.
Yup really sleepy .. Thanks .. :) :)
Post by: saleemsamer on May 11, 2010, 09:26:58 pm
Post by: Vin on May 11, 2010, 09:28:34 pm
cn u explain me y is adzels ans wrong..... because i gt the same :( ;) :)
here .. hope u get this ..
Post by: Adzel on May 11, 2010, 09:29:38 pm
Oh yes, i've been DYING, literally, to figure out how to make the locus of this.
Oct/Nov 2008, Paper 21, Q5. :)
easy...
Post by: Adzel on May 11, 2010, 09:30:42 pm
thx ~VIN1094~ and Adzel ;D
your welcome...
Post by: Vin on May 11, 2010, 09:32:32 pm
thx ~VIN1094~ and Adzel ;D
ur welcome
Okay guys im signing off too .. DO WELL !!!
Post by: Adzel on May 11, 2010, 09:35:41 pm
BEST OF LUCK TO ALL INSHALLAH!!
Post by: 6394 on May 11, 2010, 09:36:40 pm
Post by: 6394 on May 11, 2010, 09:39:59 pm
Post by: Shazizzzle on May 11, 2010, 09:48:28 pm
Post by: 6394 on May 11, 2010, 09:52:30 pm
Post by: the_grim_reaper on May 11, 2010, 10:04:37 pm
Post by: Shazizzzle on May 11, 2010, 10:24:37 pm
Guys has someone already answered question 9 oct/nov 07 paper 2 ??? Please I don't know how to do it! :(Mullay.
x^2 + 4x - 8
= x(x +4) -8
=x(x + 4 + (4/2)^2 - (4/2)^2) - 8 [Completing square method applied]
=x(x + 4 + (2)^2) -(2)^2 -8
=x(x + 2)^2 -4 -8
=x(x + 2)^2 - 12
So, (x + p)^2 + q
Therefore, p=2, q=-12.
:)
Post by: the_grim_reaper on May 11, 2010, 10:35:26 pm
By the way, SAR right guess ;D.
Post by: Shazizzzle on May 11, 2010, 10:43:49 pm
Shaz 1 final thing say if I take the coefficient of x to 5, then it'll p=2.5 and q= -14.25 right????
By the way, SAR right guess ;D.
Yes. That's correct.
Don't ask me how. :P Naeem did it like this. On one of the days you were absent. :P
haha. you've used deadman786 on chappa too ;)
Post by: the_grim_reaper on May 11, 2010, 10:47:13 pm
Post by: Shazizzzle on May 11, 2010, 10:49:48 pm
I did it in my copy but I couldn't read my writing :P. One more thing, if coefficient of x^2 isn't 1 then we first divide every number in the eq. by it????? :(
Yes, the whole thing, I believe, just like completing square method.
Post by: Shazizzzle on May 11, 2010, 10:54:25 pm
Plzzz help me here! :-S
Umm, parallel lines have the same gradient i.e coefficient of x. So... m=2.
3 is the y intercept. So, B (0, 3)
AB is 7.
7-3 = 4.
So, at B, y value is -4.
So c= -4
y=mx + c
y=2x -4
Post by: Shazizzzle on May 11, 2010, 10:55:23 pm
Post by: polltery on May 11, 2010, 10:57:12 pm
Post by: dsiddiqi11 on May 11, 2010, 11:02:14 pm
Post by: astarmathsandphysics on May 11, 2010, 11:05:21 pm
Post by: dsiddiqi11 on May 11, 2010, 11:12:36 pm
Simple answer - it is usually a triangle so after you have drawn the lines, look for a triangle
ya i knw but there could be more than one triangle, so the problem is which region to shade, so can u give me an example and briefly explain it plzzz Thanks, and By the way do u have to draw the lines or the shape is given to us
Post by: 6394 on May 12, 2010, 06:49:25 am
<o/n 09 ques 4>
answer this plz
Post by: 6394 on May 12, 2010, 06:50:41 am
Post by: holtadit on May 12, 2010, 07:07:57 am
The MS says 5k.
Post by: Vin on May 12, 2010, 07:12:36 am
-- x3/2 * 2 x5/2
8
For this when u reciprocate 1/2x^-5/2
u get 2x and +ve x^5/2 and the sign changes to multiplication..
for eg (1/2)^-1 is simply 2 .. same rule applies here
so u get
5
-- x^3/2 * 2x ^ 5/2
8
on adding the powers (as 5/8 x and 2 x are multiplied) and simplifying
u get
5
-- x4
4
Post by: Baladya on May 12, 2010, 07:14:07 am
There are 10^9 nanoseconds in 1 second.
Find the number of nanoseconds in 5 minutes, giving your answer in standard form.
I multiply 10^9 x 5 x 60 = My calculator say 3x10^12. But in mark scheme its 3x10^11????
Plz help :S :S
Post by: contraentry on May 12, 2010, 07:14:16 am
Therefore : 5y= K, Hence K*51
Thus the answer derived is = 5k
By the way, Which paper is this question from?
Post by: Vin on May 12, 2010, 07:15:25 am
How would you do this.
The MS says 5k.
whenever a power to any any number is added by 1 .. the number automatically gets multiplied by 1 .. like for eg
22
= 2 x 2= 4
22+1
= 23
= 2 x 2 x 2
= 8
and so on .. ;)
Post by: holtadit on May 12, 2010, 07:16:10 am
5y X 51 = 5y+1 (Law of indices)
Therefore : 5y= K, Hence K*51
Thus the answer derived is = 5k
By the way, Which paper is this question from?
winter 2003 thanks !
Post by: Vin on May 12, 2010, 07:17:52 am
GUYSSS PLZZZZ HELPPP!!!!
There are 10^9 nanoseconds in 1 second.
Find the number of nanoseconds in 5 minutes, giving your answer in standard form.
I multiply 10^9 x 5 x 60 = My calculator say 3x10^12. But in mark scheme its 3x10^11????
Plz help :S :S
which calci do u use .. ?? i get 3x10^11 in my calci .. try 1000000000 * 60 * 5 ..
Post by: xMilishax on May 12, 2010, 07:19:51 am
Q5 --> http://www.freeexampapers.com/FreeExamPapers.com_.php?__lo=SUdDU0UvTWF0aHMvQ0lFLzIwMDggTm92LzA1ODBfdzA4X3FwXzAyLnBkZg==
Post by: Baladya on May 12, 2010, 07:21:50 am
which calci do u use .. ?? i get 3x10^11 in my calci .. try 1000000000 * 60 * 5 ..
OMG. I did 10x10^9 not 10^9 0.0 >< OMG I m gonna fail today cuz of stupid mistakes :S :\
Post by: Vin on May 12, 2010, 07:24:20 am
easy...
do you mind explaining how ..
@ xMilishax ..Adzel has done it here .. scroll down .. but i still dont get it
https://studentforums.biz/index.php/topic,7086.510.html
@Baladya .. they'll ban u for profanity .. !!
Post by: Baladya on May 12, 2010, 07:24:55 am
Can someone pls help me with this question?
Q5 --> http://www.freeexampapers.com/FreeExamPapers.com_.php?__lo=SUdDU0UvTWF0aHMvQ0lFLzIwMDggTm92LzA1ODBfdzA4X3FwXzAyLnBkZg==
Rotate it like they said. Then put ur compass on point B and open it to point D. Rotate the compass until it meets D'
Post by: The Golden Girl =D on May 12, 2010, 07:25:38 am
plz answer ASAP!!!! ???
thx in advance
Post by: Baladya on May 12, 2010, 07:27:35 am
poeple plz help me in this .......cuz my exam is in two hours .............. how to find x if y=10 to the power of x
plz answer ASAP!!!! ???
thx in advance
This doesnt make sense. Show us the question or give a link. Is this a graph or smth?
Post by: xMilishax on May 12, 2010, 07:29:29 am
Rotate it like they said. Then put ur compass on point B and open it to point D. Rotate the compass until it meets D'
Thank you. :)
Post by: Baladya on May 12, 2010, 07:31:01 am
do you mind explaining how ..
@ xMilishax ..Adzel has done it here .. scroll down .. but i still dont get it
https://studentforums.biz/index.php/topic,7086.510.html
@Baladya .. they'll ban u for profanity .. !!
Hey Vin, but Adzels explanation is diff from the one i did. Whose right 0.0 I think mine makes more sense...
Post by: Ghost Of Highbury on May 12, 2010, 07:33:52 am
poeple plz help me in this .......cuz my exam is in two hours .............. how to find x if y=10 to the power of x
plz answer ASAP!!!! ???
thx in advance
shud i answer this or ur exam is over? i remember i have alreeady answered this..
Post by: Q80BOY on May 12, 2010, 07:35:02 am
And just a reminder, when you return from your exam please don;t come here to discuss it, we will only allow discussions after 24 hours.
Thanks and good luck! ;)
Post by: PeaceMaker on May 12, 2010, 07:35:27 am
Im going to take it in about an hour and a half, good luck all oo allah yewafegna inshallah.
Did anybody do the exam? if so is it easy? without saying the contents of the papers of course.
Post by: xMilishax on May 12, 2010, 07:36:49 am
do you mind explaining how ..
@ xMilishax ..Adzel has done it here .. scroll down .. but i still dont get it
https://studentforums.biz/index.php/topic,7086.510.html
Oh, this is different! Umm..which one is correct? I don't get it.. :\ In the mark scheme it says - arc through D radius BD, some indication that the arc is from D to D1. :-\
Pls help!
Post by: Vin on May 12, 2010, 07:39:07 am
Oh, this is different! Umm..which one is correct? I don't get it.. :\ In the mark scheme it says - arc through D radius BD, some indication that the arc is from D to D1. :-\
Pls help!
OHHHH YA YA YA i got it .. gimme 2 mins i'll explain .. ;)
Post by: Baladya on May 12, 2010, 07:40:26 am
Oh, this is different! Umm..which one is correct? I don't get it.. :\ In the mark scheme it says - arc through D radius BD, some indication that the arc is from D to D1. :-\
Pls help!
I guess mine is correct now that u said "arc" cuz his doesnt have any arcs. But i dont understand why they say radius BD ???
Post by: xMilishax on May 12, 2010, 07:46:34 am
OHHHH YA YA YA i got it .. gimme 2 mins i'll explain .. ;)
Oh yay! Thanks :)
Post by: xMilishax on May 12, 2010, 07:49:32 am
Q18 a) - May/June 2003
http://www.freeexampapers.com/FreeExamPapers.com_.php?__lo=SUdDU0UvTWF0aHMvQ0lFLzIwMDMgSnVuLzA1ODBfczAzX3FwXzIucGRm
and Q15 - O/N 2003
http://www.freeexampapers.com/FreeExamPapers.com_.php?__lo=SUdDU0UvTWF0aHMvQ0lFLzIwMDMgTm92LzA1ODBfdzAzX3FwXzIucGRm
Thanks a lot! :)
Post by: Vin on May 12, 2010, 07:50:29 am
Its easy .. how could i not get it .. they ask draw the locus of the point of 'D' .. meaning where was it initially .. at 90 o anticlockwise ..
hope the diag explains the rest .. ;)
Post by: xMilishax on May 12, 2010, 07:55:45 am
Its easy .. how could i not get it .. they ask draw the locus of the point of 'D' .. meaning where was it initially .. at 90 o anticlockwise ..
hope the diag explains the rest .. ;)
OMG! Thanks so much! By the way..where did you draw the big arc from? Jus wanna comfirm..Im bad at locus :\
Post by: Baladya on May 12, 2010, 07:56:43 am
Its easy .. how could i not get it .. they ask draw the locus of the point of 'D' .. meaning where was it initially .. at 90 o anticlockwise ..
hope the diag explains the rest .. ;)
K isn't that what i said?? U don't even need to draw the lines inside. Just put the compass on B and open it to D, then rotate to the left until it will meet D'.
Post by: Vin on May 12, 2010, 07:58:28 am
shud i answer this or ur exam is over? i remember i have alreeady answered this..
yes pls. A@di, i hav the same doubt .. :) ASAP .. =)
is it .. sqrt x {y} .. i mean it has to be .. :-\
Post by: xMilishax on May 12, 2010, 08:00:12 am
K isn't that what i said?? U don't even need to draw the lines inside. Just put the compass on B and open it to D, then rotate to the left until it will meet D'.
Yes, you were correct but the mark scheme says stuff about BD radius and so I think we need to show those lines. :)
Post by: Vin on May 12, 2010, 08:01:29 am
OMG! Thanks so much! By the way..where did you draw the big arc from? Jus wanna comfirm..Im bad at locus :\
compass at B .. draw radius BD .. :)
Post by: Ghost Of Highbury on May 12, 2010, 08:01:46 am
Could someone pls explain this too? -->
Q18 a) - May/June 2003
http://www.freeexampapers.com/FreeExamPapers.com_.php?__lo=SUdDU0UvTWF0aHMvQ0lFLzIwMDMgSnVuLzA1ODBfczAzX3FwXzIucGRm
and Q15 - O/N 2003
http://www.freeexampapers.com/FreeExamPapers.com_.php?__lo=SUdDU0UvTWF0aHMvQ0lFLzIwMDMgTm92LzA1ODBfdzAzX3FwXzIucGRm
Thanks a lot! :)
q18a) measure the side AB with a ruler. 100m = 100*100cm = 10000cm. 10000/AB = n
15) bisect angle P. make the radius from T which is 90 degree to TP. attached
Post by: Vin on May 12, 2010, 08:02:41 am
K isn't that what i said?? U don't even need to draw the lines inside. Just put the compass on B and open it to D, then rotate to the left until it will meet D'.
ok i didnt read wat u said .. n actually line BD is not required but still .. =)
Post by: xMilishax on May 12, 2010, 08:07:05 am
q18a) measure the side AB with a ruler. 100m = 100*100cm = 10000cm. 10000/AB = n
15) bisect angle P. make the radius from T which is 90 degree to TP. attached
Thanks a lot! :)
But the first answer is supposed to be 1000 :\ ???
Post by: Ghost Of Highbury on May 12, 2010, 08:10:23 am
y = 10x
x = log y
now, i know u guyz dont know log. but that is the answer, u have to give me a question like this one..
-------
Q : f(x) = 10x.
(a) Calculate f(0.5).
(b) Write down the value of f -1(1).
i dont get the "b" part
how do u find the inverse of 10x
----------------------------
Answer : if u havent learnt log. try this method
f-1(1) means, for what value of x in 10x will u get 1
answer = 0
for e.g f(x) = x+2
f-1x = x-2
f(2) = 4
put 4 in f-1x and u shud get 2
4 -2 = 2
see?
simple
@xMilishax - Yes, 10000/AB shud be equal to 1000. Measure AB with ur ruler and do this calculation 10000/AB
Post by: xMilishax on May 12, 2010, 08:15:56 am
@xMilishax - Yes, 10000/AB shud be equal to 1000. Measure AB with ur ruler and do this calculation 10000/AB
Ohh okay! But I get 8.5 cm when I measure, thats only because its not the original paper right? Otherwise I would get close to 10 I think :|
Post by: Ghost Of Highbury on May 12, 2010, 08:16:41 am
Post by: Mathewness on May 12, 2010, 09:34:32 am
Post by: ivrytwr3 on May 12, 2010, 12:13:19 pm
There is a a 3d picture of a shape with measurements on it. Below that is a squared area with the shape not in it 2d format. The question is about 'net' drawings - unfortunately i have never covered this as i was on a weeks math course and a week is a short time to squeeze the entire syllabus into!
Secondly - a picture of a straightline, marked A - B and the length is given. The question asks to put a boundry of a specific length around the line. What shape should the boundry be? Some people say a square, some a cirlce, some say it doesn't matter, a sqaure or a circle will suffice!!!
Thanks!
Post by: Vin on May 12, 2010, 12:17:22 pm
@ A@di thanks fo the explanation .. +rep .. :) gave my paper and it wa.... :-X
Post by: Ghost Of Highbury on May 12, 2010, 12:51:30 pm
Mind saying which paper ??
@ A@di thanks fo the explanation .. +rep .. :) gave my paper and it wa.... :-X
what happened? wasnt good?
Post by: The Golden Girl =D on May 12, 2010, 12:55:08 pm
what happened? wasnt good?
we r not allowed to say anthing abt it that's y he didn't continue his sentence ....chill mate !!
Post by: Vin on May 12, 2010, 12:58:10 pm
it was .. i mean im not allowed to say much about it right ?? it was good actually .. made a couple of silly errors .. !! and also not sure about a couple ov questions .. but overall i think i would get an 'A' .. i hope .. =| By the way A* is jus wen both papers are considered right .. ?
lol golden girl got before postin this one .. :)
u r takn maths too right .. ?
Post by: Ghost Of Highbury on May 12, 2010, 01:00:09 pm
we r not allowed to say anthing abt it that's y he didn't continue his sentence ....chill mate !!
I simply asked about how did they paper go. Expected good/bad, not details about the paper. I know the rules.
Post by: The Golden Girl =D on May 12, 2010, 01:02:57 pm
I simply asked about how did they paper go. Expected good/bad, not details about the paper. I know the rules.
god y do people always get me wrong :P :P :P ..well what i said is that mods and admins have always said that we r not allowed to speak ...so aparently our friend , VIN is tryin his best to abide to the rules ::) ..lol ... i didn't mean it the way u thought i did ;)
Post by: The Golden Girl =D on May 12, 2010, 01:04:00 pm
it was .. i mean im not allowed to say much about it right ?? it was good actually .. made a couple of silly errors .. !! and also not sure about a couple ov questions .. but overall i think i would get an 'A' .. i hope .. =| By the way A* is jus wen both papers are considered right .. ?
lol golden girl got before postin this one .. :)
u r takn maths too right .. ?
ya i'm takin math math too ....for me ..well i am probably the same as u .......always doin silly mistakes ..lol :P
Post by: Vin on May 12, 2010, 01:07:30 pm
lol .. :D a lot ov people lose marks because ov such mistakes =|
Post by: The Golden Girl =D on May 12, 2010, 01:08:46 pm
lol .. :D a lot ov people lose marks because ov such mistakes =|
i kno ..anyways gtg cuz of my lil bro , he's pain in the neck ...
Talk to you later
Post by: takamorinki on May 12, 2010, 02:21:37 pm
Post by: Vin on May 12, 2010, 02:34:14 pm
Paper 2 was good indeed .. :) but loosin a couple of marks .. :\
Post by: holtadit on May 12, 2010, 02:49:09 pm
TO those challenged people out there that means :
I KILLED IT !!!!!!!!!!
Post by: The Golden Girl =D on May 12, 2010, 03:01:37 pm
I STABBED PAPER 2's EYEBALLS OUT AND SPILT ITS ENTRAILS ON THE FLOOR !!
TO those challenged people out there that means :
I KILLED IT !!!!!!!!!!
i swear to god i can't stop laughin :D :D :D ;D ;D :D :) :D :D :D :D :D
Post by: BlackBunny103 on May 12, 2010, 03:07:52 pm
I STABBED PAPER 2's EYEBALLS OUT AND SPILT ITS ENTRAILS ON THE FLOOR !!
TO those challenged people out there that means :
I KILLED IT !!!!!!!!!!
ROLF
Out of curiosity, did you do well? By saying you killed it is quite ambiguous lolz ;D
Post by: Vin on May 12, 2010, 03:21:16 pm
LMAO .. XD ..
Post by: holtadit on May 12, 2010, 03:53:23 pm
ROLF
Out of curiosity, did you do well? By saying you killed it is quite ambiguous lolz ;D
Can you a kill a paper without doing well at it ?? ::)
Post by: BlackBunny103 on May 12, 2010, 04:02:38 pm
Can you a kill a paper without doing well at it ?? ::)
Lolz ;D
Post by: contraentry on May 12, 2010, 05:22:22 pm
Paper 2 was good indeed .. :) but loosin a couple of marks .. :\
±same here...
Post by: diogodji on May 12, 2010, 10:57:40 pm
For me it was much harder than previous ones i've done, anyway, got to look forward to paper 4.
Lets hope CIE don't think of making it harder aswell. >:(
Post by: Ukhti-R on May 12, 2010, 11:21:38 pm
Thank you.
Post by: Freaked12 on May 13, 2010, 12:06:56 am
Can you a kill a paper without doing well at it ?? ::)
that was fookin funny man
A AS student here -(A star in maths 2009 june)
just wanted to say the brits are the kindest people on earth when giving grades
Post by: Mathewness on May 13, 2010, 12:40:39 am
that was fookin funny man
A AS student here -(A star in maths 2009 june)
just wanted to say the brits are the kindest people on earth when giving grades
so true. We are actually quite lucky this year that this paper is considered "hard"
Come on you brits, give us them stars...
Post by: TheLonelyIsland on May 13, 2010, 02:45:17 am
Can you a kill a paper without doing well at it ?? ::)
How well do you think you did it? Do you think you lost any marks? :)
Post by: TheLonelyIsland on May 13, 2010, 02:48:38 am
Post by: contraentry on May 13, 2010, 07:42:37 am
Also question: if I get an A in paper 2, and an A in paper 4, would i get an A as my final mark or an A*??
One of my teachers once told me about the system for determining the threshold for the A* Mark;
I believe, the top 10% of each center (that is their) composite score across all papers in the subject, Its average score, for all the top 10% across all centers is the A* Threshold.
Post by: mohit1234 on May 13, 2010, 09:09:56 am
Please do not discuss the exam papers until 24 hours have passed.
Thank you.
now can we start discussing because i think 24 hours are over..
Post by: holtadit on May 13, 2010, 09:12:05 am
now can we start discussing because i think 24 hours are over..
NO!!!
Only a few hours then you can discuss.
Post by: PeaceMaker on May 13, 2010, 09:16:49 am
Post by: Amberr on May 13, 2010, 09:19:31 am
but i wanted to ask.. since its gonna be 24 hours in 20 minss..
you know the question which we had to rearrange the P=(x+3)/x.. to make x the formula.. what did you all get???
i got it wrong i think.. i got like Px-3 ???
Post by: astarmathsandphysics on May 13, 2010, 09:21:58 am
xP=x+3
xP-x=3
x(P-1)=3
x=3/(P-1)
Post by: Dibss on May 13, 2010, 09:27:58 am
P=(x+3)/xI GOT THE SAME ANSWER ;D
xP=x+3
xP-x=3
x(P-1)=3
x=3/(P-1)
so does this mean we're allowed to start discussing now?
Post by: mohit1234 on May 13, 2010, 09:30:22 am
I GOT THE SAME ANSWER ;D
so does this mean we're allowed to start discussing now?
even i got tht answer!! YAAAY!!
yes i think we are allowed
Post by: Amberr on May 13, 2010, 09:31:18 am
and for the white paint thing.. did you guys get 88.0 (3.s.f)????
ooohh.. and for the sinx-cosx= 0.5 .. did u get 66??? i spent 10 mins on the calculator .. working out everysinle value.. nothing gave it exact... so i just put 66???
im so confused.. cuz im meant to do the igcse next year but my teachers like .. oh u have tha capability to do it this year and get at least an A.. soo i did it yesterday.. and i think ive lost like 4 marks or 3 marks...
well anyways... i hope we get A*'s inshallah :)
Post by: Amberr on May 13, 2010, 09:32:13 am
even i got tht answer!! YAAAY!!
yes i think we are allowed
thats what i lost 3 marks on.. omg im so stupiddddd... why did i get such an easy question wrong????
Post by: mohit1234 on May 13, 2010, 09:33:51 am
ohh and alsoo.. you know the maximum speed for the boris guy.. did u ppl get 16.25????
and for the white paint thing.. did you guys get 88.0 (3.s.f)????
ooohh.. and for the sinx-cosx= 0.5 .. did u get 66??? i spent 10 mins on the calculator .. working out everysinle value.. nothing gave it exact... so i just put 66???
im so confused.. cuz im meant to do the igcse next year but my teachers like .. oh u have tha capability to do it this year and get at least an A.. soo i did it yesterday.. and i think ive lost like 4 marks or 3 marks...
well anyways... i hope we get A*'s inshallah :)
ya i got 16.25
and the sinx and cosx thing was 66
but fr the white paint thing i got 12pi which is something like 37.3
do u remember the white paint question(could u plz tell me)
Post by: astarmathsandphysics on May 13, 2010, 09:34:03 am
Post by: mohit1234 on May 13, 2010, 09:35:26 am
I havent been following this. Was catching up with a backlog of work. When was the exam?it was yesterday
Post by: Amberr on May 13, 2010, 09:35:44 am
ya i got 16.25
and the sinx and cosx thing was 66
but fr the white paint thing i got 12pi which is something like 37.3
do u remember the white paint question(could u plz tell me)
it was like we hade to work out the length of the minor arcs.. times it by 4...
and then add it to the circumference of the small circle.. radius 8 cm.. soo yeahh i got like 88.0
Post by: mohit1234 on May 13, 2010, 09:38:06 am
it was like we hade to work out the length of the minor arcs.. times it by 4...
and then add it to the circumference of the small circle.. radius 8 cm.. soo yeahh i got like 88.0
oh no!
i only calculated the length of the arcs and multiplied by 4...hw many marks was the question?
hw much do u think i will get for tht question??
Post by: Amberr on May 13, 2010, 09:38:40 am
gotta go study for paper 4... which is gonna kill me... OHHH
OHH and u know the inequalitys.. where did u put the R..???? like on the left side ryt.. not in the middle ryt???
Post by: saleemsamer on May 13, 2010, 09:39:12 am
it was like we hade to work out the length of the minor arcs.. times it by 4...|
and then add it to the circumference of the small circle.. radius 8 cm.. soo yeahh i got like 88.0
I got 88 too :D
Post by: Amberr on May 13, 2010, 09:39:39 am
oh no!i think it was 4 or 5 marks.. umm ull probably get like 3.. or sumthing..i have no idea.. :S
i only calculated the length of the arcs and multiplied by 4...hw many marks was the question?
hw much do u think i will get for tht question??
Post by: Kojoudeh95 on May 13, 2010, 09:40:07 am
Post by: saleemsamer on May 13, 2010, 09:40:33 am
Does any1 know what was the order of rotational symmetry??? PLZ!!! I put 1, is 1 or 0? :Pi think its 0 but not sure
Post by: Amberr on May 13, 2010, 09:40:40 am
|YAYYY.. By the way.. wht did u get for the inequalti thing.. where did u put the R??? not in the middle ryt???
I got 88 too :D
Post by: mohit1234 on May 13, 2010, 09:41:05 am
Does any1 know what was the order of rotational symmetry??? PLZ!!! I put 1, is 1 or 0? :Pit was one
Post by: Amberr on May 13, 2010, 09:41:37 am
Does any1 know what was the order of rotational symmetry??? PLZ!!! I put 1, is 1 or 0? :Pit was 1..
cuz it can never be zero.. a shape can always fit on its self once..
Post by: Kojoudeh95 on May 13, 2010, 09:42:30 am
Post by: mohit1234 on May 13, 2010, 09:42:58 am
YAYYY.. By the way.. wht did u get for the inequalti thing.. where did u put the R??? not in the middle ryt???
R was in the middle
Post by: Amberr on May 13, 2010, 09:45:23 am
ok inshallah.. paper 4 will not be as hardd
Post by: Amberr on May 13, 2010, 09:46:18 am
YAY!!!! i only got 1 mistake, i forgot to write the meter thing in standard from :'(
ohhh.. thtss good.. u sure u got everything else ryt???
Post by: mohit1234 on May 13, 2010, 09:46:41 am
NOOOO>. omg i lost 4 markss. then.. noooooooo :'( :'( :'(hope so it wont be as hard as this one
ok inshallah.. paper 4 will not be as hardd
Post by: holtadit on May 13, 2010, 09:47:41 am
I just killed the paper.
Post by: Amberr on May 13, 2010, 09:47:56 am
hope so it wont be as hard as this onei knoww.. inshallah
Post by: Kojoudeh95 on May 13, 2010, 09:48:33 am
ohhh.. thtss good.. u sure u got everything else ryt???
YUP!!! ;D
Post by: Dibss on May 13, 2010, 09:51:27 am
rotational symmetry-1
lines of symmetry -1
rearranging thing x=3/(p-1)
white paint thing = 88
maximum speed of boris - 16.25
sin cos things- 45 degrees and 66 degrees
the very last graph qs - 82 i think and 108
the inequalites R- was in the slightly large area towards the middle/right
the line parallel to the eq passing through midpoint of AB- y=-3x+14
P.S. who agrees that the paper was definitely more difficult than past papers but still went super-awesome ;D ;D
I LOOOOVED IT
Post by: Amberr on May 13, 2010, 09:53:13 am
Post by: dsiddiqi11 on May 13, 2010, 09:53:53 am
Post by: mohit1234 on May 13, 2010, 09:54:06 am
ANSWERS THAT I CAN REMEMBER:
rotational symmetry-1
lines of symmetry -1
rearranging thing x=3/(p-1)
white paint thing = 88
maximum speed of boris - 16.25
sin cos things- 45 degrees and 66 degrees
the very last graph qs - 82 i think and 108
P.S. who agrees that the paper was definitely more difficult than past papers but still went super-awesome ;D ;D
I LOOOOVED IT
i think i got the white paint one wrong...otherwise others are right
do u remember where the R was in the graph, in the middle or on the left??
Post by: Dibss on May 13, 2010, 09:54:23 am
I am pretty sure I got everything correct.i murdered it by shoving a truck of ketchup down it's throat ;D
I just killed the paper.
same! had like half an hour left to recheck all my answers :P
Post by: Amberr on May 13, 2010, 09:54:47 am
ANSWERS THAT I CAN REMEMBER:
rotational symmetry-1
lines of symmetry -1
rearranging thing x=3/(p-1)
white paint thing = 88
maximum speed of boris - 16.25
sin cos things- 45 degrees and 66 degrees
the very last graph qs - 82 i think and 108
P.S. who agrees that the paper was definitely more difficult than past papers but still went super-awesome ;D ;D
I LOOOOVED IT
i agreeeeeeeeee........ it was harddd.. but all the revision didnt go to waste.... i put my best effort :D
Post by: Amberr on May 13, 2010, 09:55:32 am
i think i got the white paint one wrong...otherwise others are right
do u remember where the R was in the graph, in the middle or on the left??
i put it on the left ??? ???
Post by: Amberr on May 13, 2010, 09:56:16 am
can someone plz just tell me one last time, will CIE do the curve thing or not?
whts the curve thing????????
wht difference does it make????? :( does tht mean if you get 66/70 its not an A*
Post by: Amberr on May 13, 2010, 09:58:27 am
Post by: Amberr on May 13, 2010, 09:59:21 am
Post by: Dibss on May 13, 2010, 10:00:48 am
i think i got the white paint one wrong...otherwise others are rightaww bummer but atleast you got the part until 37point something correct right?
do u remember where the R was in the graph, in the middle or on the left??
yep, R was in the sort of big area towards the right!
Post by: dsiddiqi11 on May 13, 2010, 10:03:36 am
Post by: mohit1234 on May 13, 2010, 10:05:40 am
aww bummer but atleast you got the part until 37point something correct right?i got R in the middle
yep, R was in the sort of big area towards the right!
was the white paint one 37.something ??? cos some people r saying its 88
Post by: holtadit on May 13, 2010, 10:07:13 am
i got R in the middle
was the white paint one 37.something ??? cos some people r saying its 88
DEFINITELY 88
Post by: dsiddiqi11 on May 13, 2010, 10:07:49 am
whts the curve thing????????
wht difference does it make????? :( does tht mean if you get 66/70 its not an A*
no look, 80% is an A but with tht curve thing a 70% could be an A, it just depends on the difficulty of the paper. look at the grade thresholds(gt) on freeexampapers.com
Post by: mohit1234 on May 13, 2010, 10:10:32 am
DEFINITELY 88wat abt R. it was in the middle or left or right??
Post by: Dibss on May 13, 2010, 10:11:34 am
i got R in the middleyep middle/right
was the white paint one 37.something ??? cos some people r saying its 88
it was 37.something+circumference of first circle = 88 <--answer
Post by: Shazizzzle on May 13, 2010, 10:17:20 am
It's either 0, 2 or 4.
And that image only turned back to it's position after one whole turn,
and...
EVERY IMAGE TURNS BACK TO ITSELF AFTER THE COMPLETE 360 deg,
So, the order or rotational symmetry was 0?
And the sinx-cosx=0.5, what do you suppose can be the range of the answers?
Also, what equation of line did you get in the intersecting lines one, the lat part?
Post by: dsiddiqi11 on May 13, 2010, 10:19:38 am
According to our teacher, order of rotational symmetry can never be 1.
It's either 0, 2 or 4.
And that image only turned back to it's position after one whole turn,
and...
EVERY IMAGE TURNS BACK TO ITSELF AFTER THE COMPLETE 360 deg,
So, the order or rotational symmetry was 0?
And the sinx-cosx=0.5, what do you suppose can be the range of the answers?
Also, what equation of line did you get in the intersecting lines one, the lat part?
i got y=3x-13, but is this the question u are talking abt
Post by: Shazizzzle on May 13, 2010, 10:21:08 am
i got y=3x-13, but is this the question u are talking abt
Umm, I'm referring to variant 2.
One thing, was the gradient of the line parallel to it 3, or -3?
Post by: haris94 on May 13, 2010, 10:21:28 am
ANSWERS THAT I CAN REMEMBER:
rotational symmetry-1
lines of symmetry -1
rearranging thing x=3/(p-1)
white paint thing = 88
maximum speed of boris - 16.25
sin cos things- 45 degrees and 66 degrees
the very last graph qs - 82 i think and 108
the inequalites R- was in the slightly large area towards the middle/right
P.S. who agrees that the paper was definitely more difficult than past papers but still went super-awesome ;D ;D
I LOOOOVED IT
i got exactly the same answers ;D
agreed, paper required more thinking but i think i (like Ari said) killed it 8)
Post by: mohit1234 on May 13, 2010, 10:22:10 am
i got y=3x-13, but is this the question u are talking abti got y=-3x+14
Post by: haris94 on May 13, 2010, 10:24:01 am
Umm, I'm referring to variant 2.
One thing, was the gradient of the line parallel to it 3, or -3?
the gradient was -3
cause the equation of parallel line was 3x+y=18
so it becomes y=18-3x
the equation finally is
y=-3x+14
Post by: dsiddiqi11 on May 13, 2010, 10:26:37 am
Umm, I'm referring to variant 2.
One thing, was the gradient of the line parallel to it 3, or -3?
i think its 3, cuz parallel lines have same gradient
Post by: Shazizzzle on May 13, 2010, 10:27:01 am
the gradient was -3
cause the equation of parallel line was 3x+y=18
so it becomes y=18-3x
the equation finally is
y=-3x+14
Wow. :/
Post by: Dibss on May 13, 2010, 10:29:32 am
Umm, I'm referring to variant 2.i did variant2 and grad was -3
One thing, was the gradient of the line parallel to it 3, or -3?
i got y=-3x+14SAME :D
i got exactly the same answers ;DWOOT WOOT ;D
agreed, paper required more thinking but i think i (like Ari said) killed it 8)
Post by: dsiddiqi11 on May 13, 2010, 10:31:10 am
Post by: haris94 on May 13, 2010, 10:34:33 am
guys for the boris speed question, i didnt multiply my answer by 2 to get the max speed, so how many marks do i get, i showed all of the working
y do u hv to multiply the answer by 2 ???
i dont remember doing that
Post by: Dibss on May 13, 2010, 10:36:23 am
guys for the boris speed question, i didnt multiply my answer by 2 to get the max speed, so how many marks do i get, i showed all of the workingum what multiplying by2?
you find alonso's total dist. which was 130
then you do 1/2 x v x 16 = 130
v=16.25
Post by: Choc.Kits on May 13, 2010, 10:44:32 am
the gradient was -3
cause the equation of parallel line was 3x+y=18
so it becomes y=18-3x
the equation finally is
y=-3x+14
Did that! Amazzzzzzing! :)
Post by: Choc.Kits on May 13, 2010, 10:46:11 am
As far as i know, i lost out on the sinx - cosx = 0.5... i messed that sh*t up....
Post by: Shazizzzle on May 13, 2010, 10:47:41 am
So... 1 or 2 marks, either way, that's sh*t. :/
Crap.
Post by: mohit1234 on May 13, 2010, 10:49:40 am
And its true, the first question, the rotational symmetry was 0. Cause you cant have a rotational symmetry of 1.
As far as i know, i lost out on the sinx - cosx = 0.5... i messed that sh*t up....
the rotational symmetry was 1. u can hve a rotational symmetry of 1!!
Post by: Shazizzzle on May 13, 2010, 10:51:28 am
Not really! If a shape only matches itself once as you go around (ie it matches itself after one full rotation) there is really no symmetry at all, because the word "Symmetry" comes from syn- together and metron measure, and there can't be "together" if there is just one thing.)
http://www.mathsisfun.com/geometry/symmetry-rotational.html
Post by: Shazizzzle on May 13, 2010, 10:53:47 am
What's done is done.
So I screwed up a question worth 2 marks. Just hope I get 1/2 of those for the working.
Let's not dwell on past mistakes. That just ruins the future too.
So, Paper4?
Shitty questions: Probability and Sequence.
That's all I fear for.
Post by: mohit1234 on May 13, 2010, 10:54:12 am
Is there Rotational Symmetry of Order 1 ?oh..then i got another one wrong :(
Not really! If a shape only matches itself once as you go around (ie it matches itself after one full rotation) there is really no symmetry at all, because the word "Symmetry" comes from syn- together and metron measure, and there can't be "together" if there is just one thing.)
http://www.mathsisfun.com/geometry/symmetry-rotational.html
hope cie give both 1 and 0 right ;)
Post by: Dibss on May 13, 2010, 11:03:26 am
from a different site >> "A" has got rotational symmetry of order 1. This is just a complicated why of saying that you can not turn "A" around to any other position so it looks the same.
So rotational symmetry order of 1 means NO rotational symmetry (we can't rotate it).
----does this mean that the first answer could be 1 OR 0 or what?
EDIT: shazizzle, looks like we both ended up at google for the same reason! haha :P
Post by: Shazizzzle on May 13, 2010, 11:06:57 am
from a website >>Is there Rotational Symmetry of Order 1? Not really! If a shape only matches itself once as you go around (ie it matches itself after one full rotation) there is really no symmetry at all, because the word "Symmetry" comes from syn- together and metron measure, and there can't be "together" if there is just one thing.)
from a different site >> "A" has got rotational symmetry of order 1. This is just a complicated why of saying that you can not turn "A" around to any other position so it looks the same.
So rotational symmetry order of 1 means NO rotational symmetry (we can't rotate it).
----does this mean that the first answer could be 1 OR 0 or what?
EDIT: shazizzle, looks like we both ended up at google for the same reason! haha :P
Haha! :P Yeah. Google FTW! XD
Okay, umm, this is for CIE to worry about.
You wrote what you thought. And It's 1 mark. So it's their problem now. :P
I think they should accept both.
Or ima march all the way down there and shove this site into their faces. XD
Post by: The Golden Girl =D on May 13, 2010, 11:15:50 am
ANywaysss.. looks like we all did good. :D atleast we all got more than 60 sa7??????
inshAllah ....
Post by: The Golden Girl =D on May 13, 2010, 11:16:13 am
yep middle/right
it was 37.something+circumference of first circle = 88 <--answer
ya i did mine in the middle
Post by: Dibss on May 13, 2010, 11:17:33 am
I think they should accept both.
Or ima march all the way down there and shove this site into their faces. XD
HAHA i'll even lend you my amazing marching boots as long as you show them both sites ;)
Post by: The Golden Girl =D on May 13, 2010, 11:18:34 am
i got y=3x-13, but is this the question u are talking abt
ya i got the same answer as urs ..lol
Post by: The Golden Girl =D on May 13, 2010, 11:18:55 am
Umm, looking forward to paper 4 now.
What's done is done.
So I screwed up a question worth 2 marks. Just hope I get 1/2 of those for the working.
Let's not dwell on past mistakes. That just ruins the future too.
So, Paper4?
sh*tty questions: Probability and Sequence.
That's all I fear for.
ya inshallah paper 4 turns out well :D ....ohh i totally agree abt the dwellin part ;)
gd luck everyone in all ur exams ;D :D.....
Post by: Borat3169 on May 13, 2010, 11:29:37 am
Post by: The Golden Girl =D on May 13, 2010, 11:32:16 am
Hey what did u guyz get for the Boris and other guyz question?? The one where they travel the same distance in same time and it wants you to find v?? I pooped that question,I got like 16. smthng plzz write the answer !!! :'(
read the previous replies and u'll kno ....but By the way ur answer is right but what equations did u use ..in other words , how did solve it ? .... i got it 18smthn which is wrong -_-
Post by: holtadit on May 13, 2010, 11:38:43 am
Post by: Dibss on May 13, 2010, 11:39:20 am
ya inshallah paper 4 turns out well :D ....ohh i totally agree abt the dwellin part ;)GOOD LUCK FOR PAPER 4
gd luck everyone in all ur exams ;D :D.....
Inshallah it'll be even better than P2 :)
Quote
Hey what did u guyz get for the Boris and other guyz question?? The one where they travel the same distance in same time and it wants you to find v?? I pooped that question,I got like 16. smthng plzz write the answer !!! CryBorat, 16.25 SMILE :)
Golden girl, you find alonso's total distance (area under the graph) and get 130m
then for boris you do 1/2 x v x16=130
v=16.25
time for me to go hit the books!
Post by: Shazizzzle on May 13, 2010, 11:40:04 am
read the previous replies and u'll kno ....but By the way ur answer is right but what equations did u use ..in other words , how did solve it ? .... i got it 18smthn which is wrong -_-
First of all, you had to calculate the distance traveled by Alonso, i.e area under the graph. Which was 130m.
As they both traveled the same distance, and in the same time too, the area under the graph of boris's graph should also be 130 m.
It was a traingle, so area = 1/2 X b X h
130 = 1/2 X 16 X v (height was v, the maximum speed)
v=16.25 m/s
OR.
Using Alonso's distance and time, you could find the average speed, 130/16 = 8.125 m/s.
Then, using the formula, (physics) (initial speed + final speed)/2 = avg. speed, you could find the final speed, i.e v m/s, using 0 m/s as the initial as he started from rest.
Both techniques are correct.
Post by: Dibss on May 13, 2010, 11:44:38 am
Take it from me; the order of rotational symmetry was ZEROthe David Rayner textbook endorsed by CIE has an example stating that a semi-circle has rotational symmetry of order 1.
order one is the same as zero!
Post by: The Golden Girl =D on May 13, 2010, 11:45:51 am
First of all, you had to calculate the distance traveled by Alonso, i.e area under the graph. Which was 130m.
As they both traveled the same distance, and in the same time too, the area under the graph of boris's graph should also be 130 m.
It was a traingle, so area = 1/2 X b X h
130 = 1/2 X 16 X v (height was v, the maximum speed)
v=16.25 m/s
OR.
Using Alonso's distance and time, you could find the average speed, 130/16 = 8.125 m/s.
Then, using the formula, (physics) (initial speed + final speed)/2 = avg. speed, you could find the final speed, i.e v m/s, using 0 m/s as the initial as he started from rest.
Both techniques are correct.
this is the only part i did okay ...then i added 10 to it for no reason ..idk...but atleast the examiner might give me half the mark ..anyways thx alot mate :D
Post by: aaliya_5 on May 13, 2010, 11:55:39 am
It was 387638956395 times harder than the past papers and I royally messed up :(
Guess I have no other choice but to work my butt off for paper 4 :/
Post by: Shazizzzle on May 13, 2010, 01:05:36 pm
I hated the paper.
It was 387638956395 times harder than the past papers and I royally messed up :(
Guess I have no other choice but to work my butt off for paper 4 :/
Good Luck! :)
Don't worry, Paper 4 will be easier!
Post by: 6394 on May 13, 2010, 01:16:44 pm
n ya INSHAALLAH we all will scor well in ppr 4
INSHAALLAH :) :) :0) :0)
Post by: contraentry on May 13, 2010, 01:26:46 pm
actually ppr 2 was really easy bt i made a lot LIKE A LOTTTT of silly mistakes :( :( :( :(
n ya INSHAALLAH we all will scor well in ppr 4
INSHAALLAH :) :) :0) :0)
Amen to that... :)
Post by: 6394 on May 13, 2010, 01:40:11 pm
Post by: Choc.Kits on May 13, 2010, 02:42:32 pm
Post by: contraentry on May 13, 2010, 03:28:08 pm
I hope they ease up on paper f4 a bit... but yo! i heard that there aint gunna be any graph questions or anything like that. i mean, like there will be, but everythings on the actual paper, so you dont need to draw the axis and stuff. is that legit?
You might need to label the axis and stuff, but draw, I don't think so. More so, I am a bit fretful about what kind of sequences question (the one at the end) that may be asked.
Post by: Shazizzzle on May 13, 2010, 03:34:06 pm
You might need to label the axis and stuff, but draw, I don't think so. More so, I am a bit fretful about what kind of sequences question (the one at the end) that may be asked.
Yeah, haven't you seen the 2009 papers?
Everything is ON the booklet! Just like a paper 2, but lengthier. :)
Post by: Vin on May 13, 2010, 03:38:39 pm
what if they give just the grid and tell u to plot a graph of a particular equations with no axis .. dont be so sure man .. :-\
Post by: Shazizzzle on May 13, 2010, 03:44:34 pm
what if they give just the grid and tell u to plot a graph of a particular equations with no axis .. dont be so sure man .. :-\
So? Make the axis. It's not rocket science. We've been doing it before.
Just like a plain sheet of graph. You know what to do. Why hesitate?
Post by: dsiddiqi11 on May 13, 2010, 03:59:51 pm
read the previous replies and u'll kno ....but By the way ur answer is right but what equations did u use ..in other words , how did solve it ? .... i got it 18smthn which is wrong -_-
i got 8 point something, i just had to do one more step, so i shud get like 4 marks out of 5.
Post by: The Golden Girl =D on May 13, 2010, 04:46:22 pm
i got 8 point something, i just had to do one more step, so i shud get like 4 marks out of 5.
ya i think so too ....for me i should half of the thing hence i might max loose two ..... anyways i have english so no more thinkin abt math ..lol .....
gd luck everyone in our english tomorrow :D
Post by: shlok tandon on May 13, 2010, 05:15:13 pm
quite a long day for me
so what preparations have u people done for english?
Post by: dsiddiqi11 on May 13, 2010, 05:48:30 pm
ya i think so too ....for me i should half of the thing hence i might max loose two ..... anyways i have english so no more thinkin abt math ..lol .....
gd luck everyone in our english tomorrow :D
i take english as a second language, even though its my first, so i have no worries at all for english. By the way i was doing november 09 paper 4, math and it was pretty easy, so i hope we get something like that on our paper 4,but slightly easier, lol. so wat english do u take.
Post by: Amberr on May 14, 2010, 04:13:15 am
Post by: maths234 on May 14, 2010, 06:29:03 am
and about the english language, is there always a summary question?
Post by: maths234 on May 14, 2010, 06:43:38 am
you know the question about the find the coordinates of the midpoint of the diagonal... there was no need to use simultaneous eq ryt>>>???? and for the gradient i wrote 3x+y=14.. doesnt the gradient stay the same... in a parallell line???
no there was no need, for me, i just substituted x and y for the co-ordinates of the point m, yes the gradient stays the same for parallel lines, its the y-intercept that is different, so in other words your answer is very correct
Post by: The Golden Girl =D on May 14, 2010, 10:16:18 am
hi, i'm new here, but I just want to know if anyone can remember the question that you had to change m^2 to mm^2 ???
and about the english language, is there always a summary question?
yup
Post by: Amberr on May 14, 2010, 02:51:31 pm
hi, i'm new here, but I just want to know if anyone can remember the question that you had to change m^2 to mm^2 ???
and about the english language, is there always a summary question?
for the m^2 to mm^2
i think i just multiplyed by 1000 cuz theres 100 cm in 1 metre. and then theres 10 mm in 1 cm .. so yeah.. i dunno.:S ???
and i dont take english lang.. cuz i did my math igcse one year earlier (this year) when im supposed to do it next year but the teacher was like no do it this year.. soo yeah.. thts why im sorry i cant help u on the english.. cuz im not doing english earlier.. and its probably late.. isnt the exam like over?? if it is.. then how did it go?????
Post by: BusinessMaNiac! ( Shizzle) on May 14, 2010, 05:07:09 pm
Cann ne one help me out in this MATHS PAPER 4 Question...
M/J 1997
Qs. 3...... i dont get b(ii
and also
Qs.9 - can ne one tell me what sequence SHCEME B is following... - i think marking scheme is wrong.
that would be Qs.9 a(ii) Scheme B.
I HATE SEQUENCES!!!
Post by: mdwael on May 14, 2010, 05:42:50 pm
In the change the subject x question, I got the correct answer but I wrote x=(correct answer) but they already wrote x= we just had to write the answer, is it ok if I scatched the printed (x=) and wrote it myself?
Also the R on the shading part I wrote R in pen not pencil is it ok? I did the shading with pencil just the R in pen.. Also the maximum speed I got it 16.25 but I dont remeber writing m/s, the unit is it fine?
Post by: Fastal on May 14, 2010, 05:56:43 pm
Hey im new to this forums and I dont want to sound like a hysteric but theres somethings in the recent paper 2 exam I want to make sure of.
In the change the subject x question, I got the correct answer but I wrote x=(correct answer) but they already wrote x= we just had to write the answer, is it ok if I scatched the printed (x=) and wrote it myself?
Also the R on the shading part I wrote R in pen not pencil is it ok? I did the shading with pencil just the R in pen.. Also the maximum speed I got it 16.25 but I dont remeber writing m/s, the unit is it fine?
everythings fine, dont freak out ;)
Post by: gold_wings on May 14, 2010, 07:19:01 pm
Post by: mdwael on May 14, 2010, 07:30:27 pm
By the way how much marks does the "time in minute and seconds" question carry, it was about that elevator in the snow or something the ii part, I got it wrong :( and I got the equation of line wrong and the midpoint wrong how much do you the marks total which I lost?
Post by: mdwael on May 14, 2010, 07:48:56 pm
for the m^2 to mm^2
i think i just multiplyed by 1000 cuz theres 100 cm in 1 metre. and then theres 10 mm in 1 cm .. so yeah.. i dunno.:S ???
and i dont take english lang.. cuz i did my math igcse one year earlier (this year) when im supposed to do it next year but the teacher was like no do it this year.. soo yeah.. thts why im sorry i cant help u on the english.. cuz im not doing english earlier.. and its probably late.. isnt the exam like over?? if it is.. then how did it go?????
Let me sum this up for you so you'll understand it better,
take 1 square meter, 1 square meter which has side 1 meter has an area of:
m x m =m^2
since one meter is 1000 mm changing from m^2 to mm^2 involves the following;
m x m = 1000mm x 1000mm = m^2
so you just had to multiply it by 1000000 and youll get an answer of 1.67 x 10^7
Post by: J.Darren on May 15, 2010, 05:44:00 am
you know the question about the find the coordinates of the midpoint of the diagonal... there was no need to use simultaneous eq ryt>>>???? and for the gradient i wrote 3x+y=14.. doesnt the gradient stay the same... in a parallell line???Mid-point Coordinates : [(X + X1) / 2 ) ,(Y + Y1) / 2 )]
Gradient of Parallel Lines are the same. So a line with equation y = -3 x + 14 will have a grdient of - 3 and y-intercept at (0, 14).
Post by: maths234 on May 15, 2010, 06:01:25 am
for the m^2 to mm^2It went okay, I'm doing all my exams earlier too, though the question was a bit tough, I spent 30 minutes trying to figure out what they were saying :-[
i think i just multiplyed by 1000 cuz theres 100 cm in 1 metre. and then theres 10 mm in 1 cm .. so yeah.. i dunno.:S ???
and i dont take english lang.. cuz i did my math igcse one year earlier (this year) when im supposed to do it next year but the teacher was like no do it this year.. soo yeah.. thts why im sorry i cant help u on the english.. cuz im not doing english earlier.. and its probably late.. isnt the exam like over?? if it is.. then how did it go?????
Post by: Falken_07 on May 15, 2010, 06:51:35 am
I have a question about finding 2 by 2 matrix for transformation
Though I'm already taught how to solve it, I think it is too long and is not worth the usual 2-3 mark given for it. So anyway, here is a summary on how the solution work:
Take the 2 coordinate of the object and their respective image
ie object--> ( 1,5 ) image--> ( -5,-1 )
object--> ( 1,2 ) image--> ( -2,-1 )
then use formula : matrix * object = image
(a b) * ( 1 ) = ( -5)
(c d) ( 5 ) ( -1)
( a+5b ) = ( -5 )
( c+5d ) = ( -1 )
and do the same for the other coordinate and finally use simultaneous equation to solve a, b, c and d
As you can see, it is quite a long procedure and I'm wondering if there is any simpler method to solve the question
Thanks in advance :)
Post by: Vin on May 15, 2010, 07:24:06 am
first of all welcome to SF !! hope u hav good time here ..
and even i use tht method .. though its quite lengthy but if u have understood it .. stick to it !! this method is really good and thers no way u may go wrong .. ;)
Post by: Falken_07 on May 15, 2010, 07:33:15 am
first of all welcome to SF !! hope u hav good time here ..
and even i use tht method .. though its quite lengthy but if u have understood it .. stick to it !! this method is really good and thers no way u may go wrong .. ;)
ok, thank you very much for the help :)
Post by: Vin on May 15, 2010, 07:42:50 am
always feel free to ask anytime !! By the way wat other subjects do u take ??
Post by: $H00t!N& $t@r on May 15, 2010, 10:08:22 am
Post by: Choc.Kits on May 15, 2010, 10:37:00 am
then i see the new co-ordinates. so if (1,0) became (0,1) and (0,1) became (1,0) my matrix for that transformation would be [0 1, 1 0]
im not sure if u can understand by that... but yea :P
Post by: Vin on May 15, 2010, 10:48:13 am
this might help ..
https://studentforums.biz/index.php/topic,5575.msg167872.html#msg167872
our friend A@di has made life easy for us .. but i cant memorise them !!
Post by: $H00t!N& $t@r on May 15, 2010, 11:12:53 am
but i cant memorise them !!lol i know what you mean! :D But i guess it's helpful to memorise it cz you'll just be wasting time on a question worth 2 marks! but if you're fast enough then it shouldnt be a problem... as for me im quite slow.. so yea. Nyway i started learning it like a month ago so i know them all now.
Post by: mdwael on May 15, 2010, 11:23:54 am
It is question 2 on page 5 (iv) part, its about transformations and tells me to describe triangle U onto triangle X and I know its shear , y axis invariant, but the shear factor is -1, not 1 as I though, can someone please describe me how to know when the shear value is negative? thanks for your help in advance :)
Post by: The Golden Girl =D on May 15, 2010, 11:25:33 am
Hey guys im preparing for P4 maths which to come in a few days and Ive been solving p4 oct/nov and there is a question I dont quite understand and I'd really appreciate your help.
It is question 2 on page 5 (iv) part, its about transformations and tells me to describe triangle U onto triangle X and I know its shear , y axis invariant, but the shear factor is -1, not 1 as I though, can someone please describe me how to know when the shear value is negative? thanks for your help in advance :)
which year?
Post by: Vin on May 15, 2010, 11:42:56 am
i think its oct/nov 2009 .. tht ques is still buggin me .. >:(
Post by: Falken_07 on May 15, 2010, 11:55:06 am
always feel free to ask anytime !! By the way wat other subjects do u take ??
Well, I'm also taking biology, chemistry, physics, computer studies, economics and EFL
(I also take examination for my native language, but its already conducted last November)
And also thanks for showing the list of the matrices for the transformation, though maybe I'll just stick to the old method :)
Post by: mdwael on May 15, 2010, 12:13:25 pm
which year?
Yes its oct/nov 2009 sorry I forget to mention the year
Post by: Ghost Of Highbury on May 15, 2010, 12:28:51 pm
Hey guys im preparing for P4 maths which to come in a few days and Ive been solving p4 oct/nov and there is a question I dont quite understand and I'd really appreciate your help.
It is question 2 on page 5 (iv) part, its about transformations and tells me to describe triangle U onto triangle X and I know its shear , y axis invariant, but the shear factor is -1, not 1 as I though, can someone please describe me how to know when the shear value is negative? thanks for your help in advance :)
w09, paper 4, 2)iv
ok this negative shear factor thingy is horrible..i cant figure it out y the move upwards is considered negative.
anyhow, its always wiser to use the matrix method
take two object and correspoding image co-ordinates..
(-4,1) --> (-4,5)
(-1,1) --> (-1,2)
check the image attached
a shear transformation matrix with y-axis is invariant is = (1 0)
(k 1)
here k = -1
Post by: Baladya on May 15, 2010, 12:34:58 pm
4)e)ii) I managed to do (i) but how can we do this?
Thanks :)
Post by: Vin on May 15, 2010, 12:40:52 pm
ans. should be 3 ..
the eqn f(x) + x – 1 = 0 means how many solutions are there for the eqn wen y=0 .. ;)
Post by: diva_sparkles on May 15, 2010, 12:52:06 pm
Hey guys im preparing for P4 maths which to come in a few days and Ive been solving p4 oct/nov and there is a question I dont quite understand and I'd really appreciate your help.
It is question 2 on page 5 (iv) part, its about transformations and tells me to describe triangle U onto triangle X and I know its shear , y axis invariant, but the shear factor is -1, not 1 as I though, can someone please describe me how to know when the shear value is negative? thanks for your help in advance :)
it is negative whn the image is toward da left!!
Post by: Baladya on May 15, 2010, 01:00:27 pm
ans. should be 3 ..
the eqn f(x) + x – 1 = 0 means how many solutions are there for the eqn wen y=0 .. ;)
Ya but how did you know it was y=0?
Post by: mdwael on May 15, 2010, 01:28:48 pm
w09, paper 4, 2)iv
ok this negative shear factor thingy is horrible..i cant figure it out y the move upwards is considered negative.
anyhow, its always wiser to use the matrix method
take two object and correspoding image co-ordinates..
(-4,1) --> (-4,5)
(-1,1) --> (-1,2)
check the image attached
a shear transformation matrix with y-axis is invariant is = (1 0)
(k 1)
here k = -1
Great thanks A LOT i never knew that a matrix gets inversed when its shifted to the other side of the equation
Post by: Vin on May 15, 2010, 01:40:33 pm
u might wanna know this too ..
https://studentforums.biz/index.php/topic,5575.msg167872.html#msg167872
Post by: Vin on May 15, 2010, 01:45:25 pm
Ya but how did you know it was y=0?
same way like u found 4 b) i)
Post by: mdwael on May 15, 2010, 02:05:05 pm
I tried and I couldnt figure out anything the MS answer says its 27W and 4W ???
Post by: Baladya on May 15, 2010, 02:40:59 pm
(ii) Now u have the radius. Imagine the line h(height of cone). It makes a right angle triangle with the radius and AO. Use Pathegeroth rule to find the height.
Post by: Ghost Of Highbury on May 15, 2010, 02:43:29 pm
W = 1/3 * x^2 * y * pi = (x^2ypi)/3
W * 27 = 9x^2ypi
27W
cii) 1/3 * pi * (2x)^2 * y = (4x^2ypi)/3
W = 1/3 * x^2 * y * pi = (x^2ypi)/3
W * 4 = (4x^2ypi)/3
4W
Post by: mdwael on May 15, 2010, 02:56:03 pm
ci ) 1/3 * pi * (3x)^2 * 3y = 9x^2y*pi
W = 1/3 * x^2 * y * pi = (x^2ypi)/3
W * 27 = 9x^2ypi
27W
cii) 1/3 * pi * (2x)^2 * y = (4x^2ypi)/3
W = 1/3 * x^2 * y * pi = (x^2ypi)/3
W * 4 = (4x^2ypi)/3
4W
I didnt understand ??? can you make it simpler please? :-\
Post by: Ghost Of Highbury on May 15, 2010, 03:01:13 pm
Height = y
Volume or W = 1/3 * x^2 * y * pi = (x^2ypi)/3
3 times --> Radius = 3x
Height = 3y
VOlume = 1/3 * pi * (3x)^2 * 3y = 9x^2y*pi
W = (x^2ypi)/3
Vol. = 9x^2y*pi
W * 27 = Vol.
27W
----------
cii) Radius = 2x
Height = y
Vol. = 1/3 * pi * (2x)^2 * y = (4x^2ypi)/3
W = (x^2ypi)/3
W * 4 = Vol.
Therefore, 4W
PS : Volume of a cone = 1/3*pi*r^2*h
Post by: mdwael on May 15, 2010, 03:15:58 pm
Radius = X
Height = y
Volume or W = 1/3 * x^2 * y * pi = (x^2ypi)/3
3 times --> Radius = 3x
Height = 3y
VOlume = 1/3 * pi * (3x)^2 * 3y = 9x^2y*pi
W = (x^2ypi)/3
Vol. = 9x^2y*pi
W * 27 = Vol.
27W
----------
cii) Radius = 2x
Height = y
Vol. = 1/3 * pi * (2x)^2 * y = (4x^2ypi)/3
W = (x^2ypi)/3
W * 4 = Vol.
Therefore, 4W
PS : Volume of a cone = 1/3*pi*r^2*h
I think I got it now but why all this working and it only carries 1 mark so shouldnt there be a quicker way maybe like 3^3=27?
Post by: Ghost Of Highbury on May 15, 2010, 03:20:49 pm
Post by: ankitd_1994 on May 15, 2010, 04:25:36 pm
n also b) ii)ya got the method bt u dont need to use it for all 3 pts only 2 will do fine
theres a great method my teacher taught me...
(y) x U = X
(a b) (-1 -4 -4 ) ( -1 -4 -4)
(c d) (1 1 3 ) = ( 2 5 7 )
multiply a b c d in matrix y to matrix U (they are the positions of the image, row 1 is x axis row 2 is y )
( (-a + b) (-4a+b) (-4a + 7b) )
( (-c+d ) (-4c +d) (-4c+ 7d) )
now solve any two equation my simultaneous method...
so, -a +b = -1 (because the position of this equation is corresponding to matrix "X", look for the colours)
-4a + b = -4
by solving u get a = 1 , b = 0
same for 'c' and 'd' ..u get d= 1 and c = -1
i dont expect u to understand but this method is really good n its really difficult for me to teach online..:(
read it n try to follow the steps while solving the paper u might get it...:) :)
Post by: mdwael on May 15, 2010, 04:44:24 pm
Post by: ivrytwr3 on May 15, 2010, 04:59:54 pm
Thank You!
Post by: gold_wings on May 15, 2010, 05:02:18 pm
Use Pythagoras' Theorem, your answer should be the square root of 3^2 - 1.5^2
Post by: ankitd_1994 on May 15, 2010, 05:05:00 pm
in May/June paper 4 2009 page 19 d(ii) part (its the last question in the paper) how do you get 1711 and 1770 I got 58 and 59 can someone please explain?the terms would be the 58th and 59th, but the values would be 1711 and 1770 when u substitute the terms in the equation to find the nth term,
n(n+1)/2, so it will be (58*59)/2 and (59*60)/2 which is 1711 and 1770
Post by: ivrytwr3 on May 15, 2010, 05:28:24 pm
Half the triangle, the base will now be 1.5 cm and the hypotenuse will be 3.
Use Pythagoras' Theorem, your answer should be the square root of 3^2 - 1.5^2
thank you, that really helped.
Post by: Shazizzzle on May 16, 2010, 10:11:01 am
Post by: Baladya on May 16, 2010, 10:15:25 am
http://www.freeexampapers.us/IGCSE/Maths/CIE/2006%20Jun/0580_s06_ms_4.pdf (http://www.freeexampapers.us/IGCSE/Maths/CIE/2006%20Jun/0580_s06_ms_4.pdf)
2)d) i get the (b) x 2 of the mark scheme, but don't understand why (a) x 40
Post by: Vin on May 16, 2010, 10:57:23 am
tht gives the area of "rectangle" BCAE ( u visualise it by 'removing' tht part from the fig. )
Post by: Baladya on May 16, 2010, 10:59:55 am
tht gives the area of "rectangle" BCAE ( u visualise it by 'removing' tht part from the fig. )
O ya so it becomes like a rectangle :D Thnanksss man :) Appreciated ;)
Post by: mdwael on May 16, 2010, 11:14:14 am
I always had problems in finding nth terms and sometimes I do but in paper O/N/07 page 10 question 9 (b) part I couldnt think of a way to find them, neither my friends. Can someone please tell us a solid guide or a way to do it there are 6 questions to find nth term in the Oct/Nov paper year 2007 question 9
We will really appreciate any help, thanks in advance :)
Post by: Vin on May 16, 2010, 11:21:14 am
Listen for nth term .. according to me is all trial and error .. u get it sometimes or u dont .. u hav to develop tht kind of thinking .. tht is by practice ..
u hav to try each and every method to get it .. i know a formula ..
dn + ( a - d )
d = Common difference between all terms.
a = First term.
only works for numbers having a common diff.
see if this helps ..
http://www.mathguide.com/lessons/SequenceArithmetic.html
someone had posted it .. i'd bookmarked it =P (sorry if wasnt great help =| )
also ..
http://everything2.com/title/How+to+find+the+nth+term+of+a+number+sequence
Post by: diva_sparkles on May 16, 2010, 11:24:16 am
This is something frustrating neither my friends or I understand ??? >:(
I always had problems in finding nth terms and sometimes I do but in paper O/N/07 page 10 question 9 (b) part I couldnt think of a way to find them, neither my friends. Can someone please tell us a solid guide or a way to do it there are 6 questions to find nth term in the Oct/Nov paper year 2007 question 9
We will really appreciate any help, thanks in advance :)
my teacher solved sum pastpapers 4 us n this wz 1 of thm! so c if u can understnd 4rm tht n +rep if thts helpful!!
Post by: diva_sparkles on May 16, 2010, 11:26:28 am
Listen for nth term .. according to me is all trial and error .. u get it sometimes or u dont .. u hav to develop tht kind of thinking .. tht is by practice ..
u hav to try each and every method to get it .. i know a formula ..
ya actualy u cant use thm 4 all of thm
Post by: nanotaha on May 16, 2010, 11:34:44 am
Maths (IGCSE)
May June 2000
Q1.
(a) (i) (ii) (iii)
(b)
How do you find them? :-\
Post by: princess12 on May 16, 2010, 11:35:50 am
Post by: nanotaha on May 16, 2010, 11:38:09 am
Why?
Post by: Vin on May 16, 2010, 11:38:19 am
Help! :(
Maths (IGCSE)
May June 2000
Q1.
(a) (i) (ii) (iii)
(b)
How do you find them? :-\
gimme some time .. i'll explain u with the diag .. ;)
Post by: nanotaha on May 16, 2010, 11:39:40 am
thanks!
Post by: Vin on May 16, 2010, 11:40:29 am
my teacher solved sum pastpapers 4 us n this wz 1 of thm! so c if u can understnd 4rm tht n +rep if thts helpful!!
avoid asking for rep .. ;) ;) you'll get it if u deserve it .. ;) ;D
Post by: princess12 on May 16, 2010, 11:41:32 am
Post by: Baladya on May 16, 2010, 12:07:47 pm
avoid asking for rep .. ;) ;) you'll get it if u deserve it .. ;) ;D
And its against the rules and look stupid :D
Post by: Vin on May 16, 2010, 12:18:09 pm
Help! :(
Maths (IGCSE)
May June 2000
Q1.
(a) (i) (ii) (iii)
(b)
How do you find them? :-\
SORRY FO THE DELAY !! .. my computer shut down unexpectedly and had to type ALL of this again !! =@
also dunno if the diag might help much..
For these types of sums always remember “y-intercept” ( c )
y = mx + c
this is a common equation for all equations of graphs ..
y-intercept means where the equations ‘cuts’ the y-axis
in this one y= x + 2 .. it cuts at 2 .. u got 1.a) ;)
so the coordinates of P would be (0,2)
for ii) if u notice Q is at y=0
so substitute 0 in 3x + 4y = 22 to find x
tht would be
3x + 4 x 0 = 22
3x = 22
x = 7.3
so coordinates of Q = (7.3 , 0)
iii) for this R is the intersection .. so tht means at tht point BOTH the equations should be equal ..
so y = x+2 (eqn1) would be equal to 3x + 4y = 22 (eqn2)
so lets find the y for R ..
rearrange 3x + 4y = 22 to
y = 22 – 3x
---------
4
As eqn1 = eqn2
22 – 3x
---------- = x + 2
4
22 – 3x = 4x + 8
7x =14
X = 2
Now put “x=2” in any of the eqn ..
U’ll get y =4
so coordinates for R = (2 , 4)
b) is a direct question .. u hav to state some inequalities that lie in the region OPRQ.
y >= 0
y =< x + 2
3x + 4y =< 22
Define this region .. for this u need understand the concept .. two eqns are already given .. the region is ‘less than’ both of them .. third would be
y >= 0 there is no negative quadrant
..
Post by: princess12 on May 16, 2010, 12:29:29 pm
urgently please fast
??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ???
Post by: Vin on May 16, 2010, 12:31:17 pm
a lot to explain .. want something in specific ??
Post by: Dibss on May 16, 2010, 12:35:55 pm
Post by: princess12 on May 16, 2010, 12:37:55 pm
Post by: Ghost Of Highbury on May 16, 2010, 12:38:41 pm
Post by: diva_sparkles on May 16, 2010, 12:40:31 pm
For shear, u gotta mention the shear factor and the invariant line. If asked, the matrix transformation too.
u can also say whthr da image moved towards rite or left!
Post by: princess12 on May 16, 2010, 12:42:49 pm
urgently please fast
??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ???
Post by: Vin on May 16, 2010, 12:45:12 pm
can any 1 explain me transformation
urgently please fast
??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ???
i asked u .. do u want something in specific ?? theres a lot im transformation .. wat dou want definition ..?/ types >>?
Post by: diva_sparkles on May 16, 2010, 12:46:51 pm
can any 1 explain me transformation
urgently please fast
??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ???
try this site
http://staff.argyll.epsb.ca/jreed/math9/strand3/transformations.htm
Post by: Kojoudeh95 on May 16, 2010, 12:54:51 pm
Post by: Vin on May 16, 2010, 12:58:07 pm
Ofc not at this stage .. only if ur too brilliant ..
solve from prolly 2000 .. thts wat i did .. ( almost done )
u'll get a good hang of solving sums .. u havta work hard .. cant avoid it =\
Post by: Kojoudeh95 on May 16, 2010, 01:00:06 pm
Post by: Vin on May 16, 2010, 01:00:53 pm
your wish ..
Post by: Kojoudeh95 on May 16, 2010, 01:02:21 pm
your wish ..
what is that supposed to mean :S....:P
Post by: Vin on May 16, 2010, 01:07:16 pm
haha .. do what u like .. =P nothin can stop u if u hav great brains !! .. =P
Post by: Dibss on May 16, 2010, 01:11:38 pm
For shear, u gotta mention the shear factor and the invariant line. If asked, the matrix transformation too.how do you get the shear factor?
Post by: gold_wings on May 16, 2010, 01:25:30 pm
Post by: Dibss on May 16, 2010, 01:38:48 pm
(distance a point moves due to shear) divided by (distance between sheared point and invariant line)Thank yoouu :]
Post by: the_grim_reaper on May 16, 2010, 02:12:28 pm
Post by: Shazizzzle on May 16, 2010, 02:49:04 pm
One final thing guys. Can anyone help me with the final two parts of the last question of paper 4 Nov 09?? (If it has already been answered then just mention the page number). By the way, anyone has any ideas on how to tackle such questions??? I mean it's all fine and great through out the paper until I reach the final parts of the last question....
It's really quite simple.
In (f), In n(n+1), you replace n by (n-1), because you want the total of the first (n-1) even numbers, not n.
So, answer= n(n-1) after simplification.
In (g), look at the first line of the Q of (e).
For Row 3, (3 x 7) + 2 + 4
i.e (number of row X first number in row) + sum of first (n-1) even numbers. [row is three, however the even numbers are 2, so n-1]
Replace the nth terms in above,
[(n) x (n^2 - n - 1)] + n(n-1)
i.e [c(i) x (d)] + (f)
Simplify, and you get n^3, which is equal to c(ii).
Post by: syedz123 on May 16, 2010, 03:16:05 pm
Post by: mdwael on May 16, 2010, 03:22:10 pm
Post by: Vin on May 16, 2010, 03:27:26 pm
IN Oct/Nov P4 2007 page 7 the last question, what does "triangle which is a plane of symmetry of the pyramid" mean? Its quesion 5 (c, (v)) part Page 7
plane of symmetry is "cutting" the pyramid exactly half should be .. HPN or MPG
Post by: mdwael on May 16, 2010, 03:30:42 pm
plane of symmetry is "cutting" the pyramid exactly half should be .. HPN or MPG
great I understood now but the MS says its PHN and PGM your are the same vertices so I guess they can be written any order right?
Post by: Vin on May 16, 2010, 03:34:50 pm
guys i've realised that my only weakness in maths is sequences...its so anoying!! i jst dunno hw to deduce da formula...i dnt get it...can any1 please help explain sequence to me...By the way am stuck on question 11 D (i) p4 may/june 09...
jus gimme 10 mins ok??
Post by: Vin on May 16, 2010, 03:36:10 pm
great I understood now but the MS says its PHN and PGM your are the same vertices so I guess they can be written any order right?
hmm .. yea absolutely .. they mean the same .. oe - Or Equivalent .. ;)
Post by: Choc.Kits on May 16, 2010, 03:36:37 pm
Post by: Vin on May 16, 2010, 03:42:33 pm
Somebody in one of the other topics posted an amazing little guide with a quick review of math. I cant seem to find that post right now but here it is.
http://freeexampapers.com/Dndex.php?d=SUdDU0UvTWF0aHMvQ0lFL1Jlc291cmNlcw==
;)
Post by: saleemsamer on May 16, 2010, 03:54:50 pm
Post by: Vin on May 16, 2010, 04:44:06 pm
guys i've realised that my only weakness in maths is sequences...its so anoying!! i jst dunno hw to deduce da formula...i dnt get it...can any1 please help explain sequence to me...By the way am stuck on question 11 D (i) p4 may/june 09...
for these kind of ques u hav to use some common sense .. even im kinda bad at sequences =\ unfortunately there are chances of this topic comin up .. because it didnt come in p2
i got this one for my mock test and i solved it by trial n error .. one thing is good tht they already mention the ans. so i try everything to get the ans
n (n+1)
= ------- + (n + 1)
2
=n2 + 3n + 2
--------------
2
ans is not (n +1 )2 so i tried adding again
=n2 + 3n + 2 n (n+1)
----------------- + ---------
2 2
=(n +1 )2
got it .. sorry i couldnt give u a proper explanation =\
Post by: 6394 on May 16, 2010, 04:55:16 pm
for these kind of ques u hav to use some common sense .. even im kinda bad at sequences =\ unfortunately there are chances of this topic comin up .. because it didnt come in p2sorry bt hw did u get
i got this one for my mock test and i solved it by trial n error .. one thing is good tht they already mention the ans. so i try everything to get the ans
n (n+1)
= ------- + (n + 1)
2
=n2 + 3n + 2
--------------
2
ans is not (n +1 )2 so i tried adding again
=n2 + 3n + 2 n (n+1)
----------------- + ---------
2 2
=(n +1 )2
got it .. sorry i couldnt give u a proper explanation =\
=n2 + 3n + 2
--------------
2
Post by: saleemsamer on May 16, 2010, 05:11:41 pm
m/j 2005 p4 q2 diagram plz and Thank You in advance :)any1 ???
Post by: princess12 on May 16, 2010, 05:15:08 pm
http://staff.argyll.epsb.ca/jreed/math9/strand3/transformations.htm
thanx
Post by: NidZ- Hero on May 16, 2010, 05:32:52 pm
Post by: princess12 on May 16, 2010, 05:35:26 pm
Post by: Vin on May 16, 2010, 05:48:21 pm
m/j 2005 p4 q2 diagram plz and Thank You in advance :)
sorry for the delay .. was havibg my dinner ! ny doubt ..
Post by: Vin on May 16, 2010, 05:49:24 pm
hey can any1 help me wid nov 2000 Q 7(a)
jus a) or everything ??
Post by: saleemsamer on May 16, 2010, 05:56:29 pm
sorry for the delay .. was havibg my dinner ! ny doubt ..;Dthx
Post by: Ghost Of Highbury on May 16, 2010, 05:59:34 pm
hey any 1 can explain me june 2003 q3part (b)
bi) .4 * .65 = 0.26
bii) Possibilities : Go and Stop or Stop and go
0.4*0.35 + 0.6*0.45 = 0.41
biii) Possibilities : Go and Stop , or Stop and Go , or Go and Go.
0.4*0.35 + 0.6*0.45 + 0.4*0.65 = 0.67
Post by: princess12 on May 16, 2010, 06:03:21 pm
can any 1 explain me oct 2007 q 6,7
urgently fast
best of luck
Post by: Ghost Of Highbury on May 16, 2010, 06:07:05 pm
Post by: Adzel on May 16, 2010, 06:12:32 pm
Thanks in advance...
Post by: princess12 on May 16, 2010, 06:15:44 pm
??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ???
Post by: Ghost Of Highbury on May 16, 2010, 06:27:36 pm
1cm:2m
therefore AB = 26m/2m = 13 cm
BD = 30m/2m = 15 cm
Angle A shud be 80 degree.
aii) Measure them with ur protractor.
aiii) Bisect the angle DAB and extend it till it intersects the trapezium.
aiv) Draw the perpendicular bisector of AD.
av) check the attached diagram.
bi) Sine rule. (Sin D)/26 = (Sin 80)/30
Sin D/26 = 0.032826925
sin D = 26*0.032826925 = 0.8535
D = sin-1 0.8535 = 58.6 degree ~ 59 degree.
bii) Angle BDC = 100-58.6 = 41.4
(BC)^2 = 182 + 302 - 2*18*30*cos 41.4 = 1224 - 810.11 = 414
BC =
biii) area of triangle ADB + BDC = 0.5 * 26 *30sin'41.4' + 0.5 *18* 30sin'41.4' = 436
will answer the 7th question soon
Post by: princess12 on May 16, 2010, 06:33:45 pm
what about q 7
Post by: Dark Prince on May 16, 2010, 06:43:39 pm
Post by: Ghost Of Highbury on May 16, 2010, 06:44:41 pm
o/n 2007 p4 q3 (explaination please)
Thanks in advance...
Ans 3ai) Point C --> Its x-co-ordinate is 0 and it lies in the curve y = x^2 + 1.
thus, just substitute the value x=0 in the equation --> y = 0^2 + 1 = 1
C --> (0,1)
3aii) with y-axis --> y = 4 - x.
any point in y-axis has the co-ordinate x=0.
apply x=0 in y = 4-x --> y = 4-0
thus, with y-axis --> (0,4)
with x-axis --> y = 4-x
any point in x-axis has y-co-ordinate = 0
apply y=0 in y = 4-x
0 = 4-x
x = 4
point --> (4,0)
b) y = mx + c , here m = gradient and c is y intercept.
write y = 4-x in this form
y = -x + 4 or y = -1(x) + 4
here m = -1
gradient = -1
c) this means find the x-values for which the point on the curve has a negative gradient. in this, a parabola, all points in the part of the curve in the second quadrant has a negative gradient. Thus, when x<0, gradient = negative.
d) the two graphs are y = x^2 + 1 and y = 4-x
meaning , x^2 + 1 = 4-x
x^2 + 1 -4 +x = 0
x^2 +x - 3 = 0
------------------
e) apply x = +/-
u shud get 1.3 and -2.3
The answers i.e 1.3 and -2.3 are the x-cordinates of the point B and A respectively.
y = 4-x
y = 4-1.3 = 2.7
y = 4-x
y = 4+2.3 = 6.3
A - (-2.3, 6.3) B - (1.3, 2.7)
(x1+x2)/2 = (-2.3+1.3)/2 = -0.5
(y1+y2)/2 = (6.3+2.7)/2 = 4.5
midpoint = (-0.5,4.5)
Post by: the_grim_reaper on May 16, 2010, 06:48:27 pm
Quote
for these kind of ques u hav to use some common sense .. even im kinda bad at sequences =\ unfortunately there are chances of this topic comin up .. because it didnt come in p2
i got this one for my mock test and i solved it by trial n error .. one thing is good tht they already mention the ans. so i try everything to get the ans
n (n+1)
= ------- + (n + 1)
2
=n2 + 3n + 2
--------------
2
ans is not (n +1 )2 so i tried adding again
=n2 + 3n + 2 n (n+1)
----------------- + ---------
2 2
=(n +1 )2
got it .. sorry i couldnt give u a proper explanation =\
Let me take a shot at this.
All right, in the previous part it is stated that the formula for the nth term is n(n+1)/k where we've found k to be 2.
So, if n is n LOL then its n(n+1)/2 and if n is (n+1) so we have (n+1)((n+1)+1)/2 (replace n by n+1 since that is the nth term here)..
Next just add them
n(n+1) (n+1)(n+2)
= ------- + -----------
2 2
= (n^2+n) + (n^2+2n+n+2)
--------------------------
2
= n^2+n^2+n+2n+n+2
----------------------
2
= 2n^2+4n+2
-------------
2
Taking 2 as common, you have =2(n^2+2n +1)
------------
2
After simplification, you have n^2+ 2n +1 which is simplified becomes (n+1)(n+1) which is equal to (n+1)^2
As far sequences are concerned, we all suck at em' mate. It's a universal issue ;D.
Post by: Adzel on May 16, 2010, 06:54:46 pm
Ans 3ai) Point C --> Its x-co-ordinate is 0 and it lies in the curve y = x^2 + 1.
thus, just substitute the value x=0 in the equation --> y = 0^2 + 1 = 1
C --> (0,1)
3aii) with y-axis --> y = 4 - x.
any point in y-axis has the co-ordinate x=0.
apply x=0 in y = 4-x --> y = 4-0
thus, with y-axis --> (0,4)
with x-axis --> y = 4-x
any point in x-axis has y-co-ordinate = 0
apply y=0 in y = 4-x
0 = 4-x
x = 4
point --> (4,0)
b) y = mx + c , here m = gradient and c is y intercept.
write y = 4-x in this form
y = -x + 4 or y = -1(x) + 4
here m = -1
gradient = -1
c) this means find the x-values for which the point on the curve has a negative gradient. in this, a parabola, all points in the part of the curve in the second quadrant has a negative gradient. Thus, when x<0, gradient = negative.
d) the two graphs are y = x^2 + 1 and y = 4-x
meaning , x^2 + 1 = 4-x
x^2 + 1 -4 +x = 0
x^2 +x - 3 = 0
------------------
e) apply x = +/-/2a)
u shud get 1.3 and -2.3
The answers i.e 1.3 and -2.3 are the x-cordinates of the point B and A respectively.
y = 4-x
y = 4-1.3 = 2.7
y = 4-x
y = 4+2.3 = 6.3
A - (-2.3, 6.3) B - (1.3, 2.7)
(x1+x2)/2 = (-2.3+1.3)/2 = -0.5
(y1+y2)/2 = (6.3+2.7)/2 = 4.5
midpoint = (-0.5,4.5)
Thanx
Post by: Ghost Of Highbury on May 16, 2010, 06:57:22 pm
thanxs
what about q 7
typing it, will take 5 minutes.
Post by: Ghost Of Highbury on May 16, 2010, 07:13:16 pm
cii) A transformation matrix. Reflection:
1. reflection in ml y=x it's (0 1)
(1 0)
https://studentforums.biz/index.php/topic,1432.15.html (6th post)
di) arrange 2 sets of co-ordinates of the triangle veritcally to form a matri
(8 10) * (0.5 0) = (4 5)
(6 12) (0 0.5) (3 6)
do the same with (6,10) and ull get the matrix (3)
(5)
so the new co-ordinates are
(8,6) --> (4,3)
(10,12)--> (5,6)
(6,10) --> (3,5)
plot them.
if u observe carefully, ull see dii) it is an enlargement of factor 0.5 and the center (0,0)
e) 0.5*10 = 5
0.5 * 8 = 4
0.5* 6 = 3
((5,12) (4,6)(3,10))
Post by: Vin on May 16, 2010, 07:13:29 pm
hey can any1 help me wid nov 2000 Q 7(a)
a) Translation ( - 3, -4)
b) tan x = 4.6/1.4
x = tan-1 73.1
c) i) height of larger / height of smaller = 7/5 = 1.4
ii)look for the blue lines .. meet at x so x = 10
(10, 0)
d) i) A = ½ * 4.8 * 1.4
= 3.36cm2
ii) very tricky !!
for an equation in terms of y=x
1.4/4.8
=0.29
y=0.29x
meaning x is 0.29 times y
e)k2 = 64 ..we are dealing with area
k = 8
f)hypo of T z2= 1.422+4.82
=5
hypo of similar triangle = k * 5
= 8 * 5
Post by: Ghost Of Highbury on May 16, 2010, 07:23:05 pm
Quote
Thanx
ur welcome.
Post by: Dark Prince on May 16, 2010, 07:25:17 pm
Can some1 tell me how to do part (e) of this Qs....(attached below)....tnkx
can some1 now do my Q....which i ve posted half an hour bfore.......if an1 knws how to do it...lol
Post by: astarmathsandphysics on May 16, 2010, 07:39:51 pm
Do d minus cii
Post by: Dark Prince on May 16, 2010, 07:52:58 pm
can some1 now do my Q....which i ve posted half an hour bfore.......if an1 knws how to do it...lol
Do d minus cii
thnkx...sir...can u xplain
Post by: Adzel on May 16, 2010, 08:00:17 pm
Post by: Vin on May 16, 2010, 08:05:13 pm
Got it !! quite easy ..
a) is quite direct ..
for such kinda ques wat i always do is look for the units .. for eq in this one..
they hav asked Calculate the number of cubic metres .. 3 measurements hav to be multiplied (this is jus a tip .. this is how i under the ques)
so for this vol = 0.3 m x 1.2 x 3 m/min x 60 (for 1 hour)
= 64.8 cm3
-----------------------------------
b) same method as the previous ..
first
vol = 0.8m x 1.2m x 15 m/min x 60
= 864 cm3
for % , difference is 864 - 64.8 = 799.2
per cent = diff/original x 100
= 799.2
--------- x 100
64.8
= 1230 %
-----------------------------------
c) firstly always remember to convert ur units to units asked in ques..
1.3 mm = 0.0013m
vol = pi rrh
2 = pi r2 x 0.0013
on solvin = 22.1 m
-----------------------------------
d) take the length as L ..
surface area = 50.4/0.12
= 420 m2
SA = (0.8 x L) + (1.2 x L) + (0.8 x L)
420 = 0.8L + 1.2L + 0.8L
420 = 2.8 L
L = 150m .. done !! ;)
Post by: mdwael on May 16, 2010, 08:27:02 pm
Sorry for asking this here but Im new and I didnt find a place to post it..
Post by: haris94 on May 16, 2010, 08:35:29 pm
the paper was out of 100 this year :)
none of the pages were missing from your friend's paper
Post by: Vin on May 16, 2010, 09:49:33 pm
I have a question I dont really think its maths but Im going to say it anyway. This is about my friend who did IT exam few days ago, well he seems to have forgotten to check the number of pages in his paper, only then after the exam had finished that he realized 2 pages worth 20 marks were missing from his paper which is out of (120) he got approximately 70 so will his mark be 70/100? or they wont forgive him and his mark will be 70/120?
Sorry for asking this here but Im new and I didnt find a place to post it..
post here from now on .. ;)
https://studentforums.biz/index.php/board,78.0.html
Post by: the_grim_reaper on May 16, 2010, 10:52:38 pm
Post by: Vin on May 17, 2010, 06:35:04 am
ur talking about Q2 right ?
see NOT necessarily it has to be ONLY x and n .. if u hav solved 2 c)iii) the answer deduced is y=20x + 5 and not jus y=x u getting my point .. ?? be confidant while solving such sums and solve them twice so that u r sure of it .. By the way d ii) is jus factorisation right ? so r u talking abt c)iii) ??
Post by: $H00t!N& $t@r on May 17, 2010, 07:32:48 am
Post by: Vin on May 17, 2010, 07:50:02 am
y=(m-2n) (m+2n)
substitute
=[(2x + 3) -2(x - 1)] [(2x + 3) +2(x + 1)]
expand
= (2x + 3 - 2x + 2) ( 2x + 3 + 2x - 2)
multiply each number and variable from the first bracket to the second ..
= (2x + 3 - 2x + 2) ( 2x + 3 + 2x - 2)
(2x + 3 - 2x + 2) ( 2x + 3 + 2x - 2)
(2x + 3 - 2x + 2) ( 2x + 3 + 2x - 2)
(2x + 3 - 2x + 2) ( 2x + 3 + 2x - 2)
u get
= 4x2 + 6x + 4x2 - 4x + 6x + 9 + 6x - 6 - 4x2 - 6x - 4x2 + 4x + 4x + 6 + 4x - 4
cancel out similar +ve and -ve numbers
rearranging
= 6x + 6x + 4x + 4x + 9 - 4
= 20x + 5
Post by: $H00t!N& $t@r on May 17, 2010, 08:03:00 am
Post by: Vin on May 17, 2010, 08:09:40 am
you can do it that way too .. ultimately u hav to factorise in the form of (a + b) ( a - b) .. jus one more step adds up .. finally u get the same ans .. safer method to do is the one i mentioned .. ;)
Post by: $H00t!N& $t@r on May 17, 2010, 08:15:13 am
you can do it that way too .. ultimately u hav to factorise in the form of (a + b) ( a - b) .. jus one more step adds up .. finally u get the same ans .. safer method to do is the one i mentioned .. ;)k ill keep that in mind ;)
Post by: key04 on May 17, 2010, 09:37:02 am
I have a question 4 maths paper 4.............
how to do ques 4 of may june 2006???????
anyone have any idea to do so??????
plz i need help urgently...........
Thanks
Post by: Ghost Of Highbury on May 17, 2010, 10:13:41 am
Post by: saleemsamer on May 17, 2010, 12:19:25 pm
Post by: Choc.Kits on May 17, 2010, 12:22:09 pm
November 2009, Paper 4, Question 7 (c)(i) and (ii)
Thank you!
Post by: Ghost Of Highbury on May 17, 2010, 12:23:47 pm
Hey guys. Im having trouble on a question. Its:
November 2009, Paper 4, Question 7 (c)(i) and (ii)
Thank you!
Radius = X
Height = y
Volume or W = 1/3 * x^2 * y * pi = (x^2ypi)/3
3 times --> Radius = 3x
Height = 3y
VOlume = 1/3 * pi * (3x)^2 * 3y = 9x^2y*pi
W = (x^2ypi)/3
Vol. = 9x^2y*pi
W * 27 = Vol.
27W
----------
cii) Radius = 2x
Height = y
Vol. = 1/3 * pi * (2x)^2 * y = (4x^2ypi)/3
W = (x^2ypi)/3
W * 4 = Vol.
Therefore, 4W
PS : Volume of a cone = 1/3*pi*r^2*h
Post by: saleemsamer on May 17, 2010, 12:28:15 pm
O/N 06 p4 q5 b and c with explanation plz ???any1?
Post by: Ghost Of Highbury on May 17, 2010, 12:29:40 pm
O/N 06 p4 q5 b and c with explanation plz ???
bi) Hits , Hits and Hits. = 1/3*1/3*1/3 = 1/27
bii) The probability that she never hits is 2/3*2/3*2/3 = 8/27
1 - 8/27 = 19/27
c)i) Hits in 4th throw = Doesnt hit, Doesnt Hit, Doesnt Hit, Hits.
Doesnt hit = 1- 1/4 = 3/4
3/4 * 3/4 * 3/4 * 1/4 = 27/256
cii) This means that he "Doesnt hit" till the nth throw. Till the nth throw means that he doesnt hit for the first (n-1)th throw.
LIke (ci), u multiply 3/4 for (n-1) times and multiply it with 1/4
Therefore, (3/4)(n-1) * 1/4
Post by: saleemsamer on May 17, 2010, 12:31:36 pm
bi) Hits , Hits and Hits. = 1/3*1/3*1/3 = 1/27
bii) The probability that she never hits is 2/3*2/3*2/3 = 8/27
1 - 8/27 = 19/27
thx but wat bout c? :)
Post by: Ghost Of Highbury on May 17, 2010, 12:32:58 pm
Quote
bi) Hits , Hits and Hits. = 1/3*1/3*1/3 = 1/27
bii) The probability that she never hits is 2/3*2/3*2/3 = 8/27
1 - 8/27 = 19/27
thx but wat bout c?
check again.
Post by: saleemsamer on May 17, 2010, 12:33:51 pm
check again.lol Thank You :D
Post by: Ghost Of Highbury on May 17, 2010, 12:45:37 pm
lol Thank You :D
No problemo
Post by: Choc.Kits on May 17, 2010, 12:53:36 pm
Radius = X
Height = y
Volume or W = 1/3 * x^2 * y * pi = (x^2ypi)/3
3 times --> Radius = 3x
Height = 3y
VOlume = 1/3 * pi * (3x)^2 * 3y = 9x^2y*pi
W = (x^2ypi)/3
Vol. = 9x^2y*pi
W * 27 = Vol.
27W
----------
cii) Radius = 2x
Height = y
Vol. = 1/3 * pi * (2x)^2 * y = (4x^2ypi)/3
W = (x^2ypi)/3
W * 4 = Vol.
Therefore, 4W
PS : Volume of a cone = 1/3*pi*r^2*h
Thanks a billion for that reply! I owe you ;)
Post by: Ghost Of Highbury on May 17, 2010, 12:58:13 pm
Post by: Mr.DitD on May 17, 2010, 02:39:04 pm
Can some1 please explain this question:
(c) A different cone, with radius x and height y, has a volume W.
Find, in terms of W, the volume of: (ii) a cone of radius 2x and height y.
http://www.freeexampapers.us/IGCSE/Maths/CIE/2009%20Nov/0580_w09_qp_4.pdf Q7 part (c)
???
Post by: Vin on May 17, 2010, 02:40:50 pm
Hello everyone!!!
Can some1 please explain this question:
(c) A different cone, with radius x and height y, has a volume W.
Radius = X
Height = y
Volume or W = 1/3 * x^2 * y * pi = (x^2ypi)/3
3 times --> Radius = 3x
Height = 3y
VOlume = 1/3 * pi * (3x)^2 * 3y = 9x^2y*pi
W = (x^2ypi)/3
Vol. = 9x^2y*pi
W * 27 = Vol.
27W
----------
cii) Radius = 2x
Height = y
Vol. = 1/3 * pi * (2x)^2 * y = (4x^2ypi)/3
W = (x^2ypi)/3
W * 4 = Vol.
Therefore, 4W
PS : Volume of a cone = 1/3*pi*r^2*h
Post by: Mr.DitD on May 17, 2010, 03:02:34 pm
[
I understand that Vol. = 1/3 * pi * (2x)^2 * y
But i dont know how it becomes: (4x^2ypi)/3
Can u please explain furthur if possible? Thanks a lot!!
Post by: Ghost Of Highbury on May 17, 2010, 03:22:29 pm
I understand that Vol. = 1/3 * pi * (2x)^2 * y
But i dont know how it becomes: (4x^2ypi)/3
Can u please explain furthur if possible? Thanks a lot!!
(2x)^2 = 4x^2.
(4x^2 * pi * y )/3 = (4x^2ypi)/3
Post by: Mr.DitD on May 17, 2010, 04:21:35 pm
(2x)^2 = 4x^2.
(4x^2 * pi * y )/3 = (4x^2ypi)/3
THANKS A LOT!!!! :D
Post by: princess12 on May 17, 2010, 04:28:57 pm
urgently fast plaese
Post by: Dibss on May 17, 2010, 04:34:14 pm
can any 1 explain me oct 2009 paper 4 question 1any particular subpart or the whole question?
urgently fast plaese
Post by: princess12 on May 17, 2010, 04:35:10 pm
Post by: Dibss on May 17, 2010, 04:42:17 pm
Post by: princess12 on May 17, 2010, 04:42:40 pm
Post by: Ghost Of Highbury on May 17, 2010, 04:51:49 pm
can any 1 explain me oct 2009 paper 4 question 1
urgently fast plaese
1a )i) 2/7 * x = 2.4
2x/7 = 2.4
2x = 16.8
x = 8.4
1aii) 8.4/20 * 100 = 42%
1b) 8/12 * 9 = 6kg
1c) Mass of fruits = 3/12 * 9 = 2.25
Price = 3/7 * 8.4 = 3.6
2.25 Kg = $3.6
1kg = 3.6/2.25 = 1.6
1d) Let the cost of the previous week be x
(25% of x) + x = 2.4
25x/100 + x = 2.4
125x/100 = 2.4
125x = 240
x = 240/125 = 1.92
Post by: princess12 on May 17, 2010, 04:59:20 pm
good luck for all subjects
Post by: Dibss on May 17, 2010, 05:11:36 pm
whole question please with briefly description
whole question please with briefly descriptionO/N 09 P4
1.
a)meat : vegetables : fruit = 2 : 2 : 3.
total parts =2+2+3=7
2 parts (meat) cost $2.4
X=total cost
2/7X=2.4
x=7/2 x 2.4= $8.4
aii) 8.4/20x100%= 42%
b)meat : vegetables : fruit = 1 : 8 : 3.
8+1+3= 12parts = total mass is 9 kg.
mass of the vegetables = 8/12x9 = 6kg
c) cost of fruits = 3/7x8.4 = $3.6
mass of fruits = 3/12x9 = 2.25kg
cost per kg = 3.6/2.25 = $1.6
d)$2.40, is an increase of 25% on the cost the previous week
cost of the meat the previous week = X
125/100 of X = 2.4
X = 2.4 x 100/125 = $1.92
hope that helps :]
EDIT : omg i am so sorry for the late reply! I clicked ‘post’ and then my net started acting up refusing to work :/ I’d been hoping that the post had appeared before my net went haywire but apparently that didn’t happen :|
Post by: big mac on May 18, 2010, 12:18:53 am
http://www.freeexampapers.us/IGCSE/Maths/CIE/2002%20Nov/0580_w02_qp_3.pdf
Q3 June 2003:
http://www.freeexampapers.us/IGCSE/Maths/CIE/2003%20Jun/0580_s03_qp_3.pdf
Q3 (b) (d) + Q5 + Q6 (b) Novermber 2003:
http://www.freeexampapers.us/IGCSE/Maths/CIE/2003%20Nov/0580_w03_qp_3.pdf
Q1 + Q2 (a) (b) (d)+ Q5 (b) Novermber 2004:
http://www.freeexampapers.us/IGCSE/Maths/CIE/2004%20Nov/0580_w04_qp_3.pdf
Q8 + Q9 (b) June 2004:
http://www.freeexampapers.us/IGCSE/Maths/CIE/2004%20Jun/Mathematics%20Paper%203.pdf
Q1 (ii) (d) (c) June 2005:
http://www.freeexampapers.us/IGCSE/Maths/CIE/2005%20Jun/Mathematics%20Paper%203.pdf
Sorry, I know this looks a lot, but most of these questions are direct questions like fast to do, but there are just some which include graphs, transformation, which I am clueless about, so I had to put in the whole question, you don't have to do all the questions even one will be great! P.S this is core theory!
Post by: LM on May 18, 2010, 06:36:15 am
and all of them comes from Nov 07/paper 4
http://www.freeexampapers.us/IGCSE/Maths/CIE/2007%20Nov/0580_w07_qp_4.pdf
here are the question :
Q2 (a)(vi)
Q3 (b) (c) (f)
Q4 (b) (c)
Q5 (b) (c)(v)
Q6 (b)(ii)(iii)
Q7 (d)(ii) (e)
Q8 (b)(c)(d)(e)
Q9 (b)(v)(vi) (d)
Please answer it ASAP!
Tomorrow is the exam!!
Post by: Mr.DitD on May 18, 2010, 08:26:24 am
What is the probable A* mark in this year's Maths IGCSE? I think I will get 64 out of 70 so is there any chance that I get an A*?!??
Thanks!
Post by: Ghost Of Highbury on May 18, 2010, 10:07:27 am
Q4 + Q5 (b) + Q8 November 2002:Ans 4) a)i) Reflection in x-axis.
http://www.freeexampapers.us/IGCSE/Maths/CIE/2002%20Nov/0580_w02_qp_3.pdf
Q3 June 2003:
http://www.freeexampapers.us/IGCSE/Maths/CIE/2003%20Jun/0580_s03_qp_3.pdf
Q3 (b) (d) + Q5 + Q6 (b) Novermber 2003:
http://www.freeexampapers.us/IGCSE/Maths/CIE/2003%20Nov/0580_w03_qp_3.pdf
Q1 + Q2 (a) (b) (d)+ Q5 (b) Novermber 2004:
http://www.freeexampapers.us/IGCSE/Maths/CIE/2004%20Nov/0580_w04_qp_3.pdf
Q8 + Q9 (b) June 2004:
http://www.freeexampapers.us/IGCSE/Maths/CIE/2004%20Jun/Mathematics%20Paper%203.pdf
Q1 (ii) (d) (c) June 2005:
http://www.freeexampapers.us/IGCSE/Maths/CIE/2005%20Jun/Mathematics%20Paper%203.pdf
Sorry, I know this looks a lot, but most of these questions are direct questions like fast to do, but there are just some which include graphs, transformation, which I am clueless about, so I had to put in the whole question, you don't have to do all the questions even one will be great! P.S this is core theory!
aii) Anti-clockwise rotation 90 degree center O
b) Check the diagram attached.
Ans 5b)i) The volume of the prism = VOlume of cuboid/2. because the prism is half of the cuboid
Volume of Cuboid = 72cm^3.
Thus, volume of prism = 36 cm^3.
5bii) AF*FG.
AF =
FG = 6cm.
Thus area = 6*5 = 30cm^2
ans8a) roughly measure the distance AB , shud be around 8cm. Multiply it with 30. Answer : Around 240km
8b) 2nd DIagram (part of the circle of radius 5cm Center points A and B)
c) 2nd Diagram (full circle of radius 5cm from center T)
June 2003.
3ai) 7*25 = 175
3aii)25b
3aiii) 100 cents = 1 dollar
175 cents = 1.75 dollars.
3aiv) 25b/100 = 0.25b
3b) i) c= T/n
ii) Cost of one bar of chocolate.
3c) i) 8 books - $36
1 book = 36/8 = $4.5
3cii) 7 books = 36-6.6 = 29.4
1 book = 29.4/7 = $4.2
3ciii) A = x/y
3civ) A = (x-1)/(y-7)
Nov 2003
ans 3b) i) Volume of cylinder = pi*r2*h = 100pi * 14 = 1400pi = 4400 (approx)
ii) 4400 + 6000 = 10,400cm^3.
iii) 25* 30*x = 10400 ---> x = 10400/(25*30) = 13.9cm.
3d doesnt exist.
ans5) (1,7) --> (7,3)
(1,7) + (6,-4) = (7,3)
x = 6
y = -4
5bi) Clockwise rotation of 180 degree about the point(2.5,6)
5bii) Enlargement : Center : (1,7). S.F = 3
5ci) 3/2 * 2 = 3
cii) 4.5*6 = 27
3/27 = 1/9
d) (7-1)/(1-10) = 6/-9 = -0.66666...
Ans6b) i) 2x+3x+1 + (y) = 9x+4
y = 9x+4-5x-1 = 4x+3
bii) 9x+4 = 49
9x = 45
x = 5cm
sides : 10, 16, 23.
Post by: Ghost Of Highbury on May 18, 2010, 10:12:19 am
Hi again,
What is the probable A* mark in this year's Maths IGCSE? I think I will get 64 out of 70 so is there any chance that I get an A*?!??
Thanks!
yes, provided u have do the other paper well..
Post by: Saladin on May 18, 2010, 10:46:35 am
yes, provided u have do the other paper well..
Which question are you up to?
Post by: Ghost Of Highbury on May 18, 2010, 11:06:06 am
I have so many questions to ask all of you..
and all of them comes from Nov 07/paper 4
http://www.freeexampapers.us/IGCSE/Maths/CIE/2007%20Nov/0580_w07_qp_4.pdf
here are the question :
Q2 (a)(vi)
Q3 (b) (c) (f)
Q4 (b) (c)
Q5 (b) (c)(v)
Q6 (b)(ii)(iii)
Q7 (d)(ii) (e)
Q8 (b)(c)(d)(e)
Q9 (b)(v)(vi) (d)
Please answer it ASAP!
Tomorrow is the exam!!
@Engraved/Dude - Start solving these...ill join u soon, solving the previous ones posted by "big mac"
Post by: LM on May 18, 2010, 11:09:35 am
@Engraved/Dude - Start solving these...ill join u soon, solving the previous ones posted by "big mac"I did do the whole paper...
those are the only questions left...
you see I need all the help....
Post by: Vin on May 18, 2010, 11:17:41 am
I did do the whole paper...
those are the only questions left...
you see I need all the help....
i'd typed out till ques 6 !!.. im using my laptop n it shut down unexpectedly !!! =@ aargh !! all waste im sorry i might not be able to help i need to study =\
Post by: Ghost Of Highbury on May 18, 2010, 11:23:12 am
I did do the whole paper...
those are the only questions left...
you see I need all the help....
2avi) this means that the order shud be like this : Not from 5th grade, not from 5th grade, from 5th grade
Students not from 5th grade = 24. Total = 28
first student not from 5th grade = 24/28
second student not from 5th grade = 23/27 (23 because 1 student has already been picked, 28-1 = 27)
third student is a fifth grader = 4/26 (26 because 2 students hav already been picked)
(24/28)^2 * 4/26 = 92/819
3b) arrange it in the form of y = mx + x where 'm' is the gradient and 'c' is the y-intercept.
y = 4-x ----> y = -x + 4 ---> y = -1(x) + 4
thus m = -1.
3c) this means find the x-values for which the point on the curve has a negative gradient. in this, a parabola, all points in the part of the curve in the second quadrant has a negative gradient. Thus, when x<0, gradient = negative.
3f) apply x = +/-
u shud get 1.3 and -2.3
The answers i.e 1.3 and -2.3 are the x-cordinates of the point B and A respectively.
y = 4-x
y = 4-1.3 = 2.7
y = 4-x
y = 4+2.3 = 6.3
A - (-2.3, 6.3) B - (1.3, 2.7)
(x1+x2)/2 = (-2.3+1.3)/2 = -0.5
(y1+y2)/2 = (6.3+2.7)/2 = 4.5
midpoint = (-0.5,4.5)
4b) Volume of water in the first diagram = pi*8^2*8 = 1608.5
Total volume of the two spheres = 180*2 = 360cm^3
Total volume of spheres and water = 1968.5
pi*8^2*h = 1968.5
h = 1968.5/64pi = 9.79
4c) 4.8g = 1cm^3
1000g = 1000/4.8 = 208.33cm^3
4/3pi*r^3 = 208.33
r = cube root of 49.73 = 3.67
5b) 2*0.5*8×’5.74’+2*0.5*6×’6.32’ +8×6 = 131.84
5c) the triangle PHN divides the pyramid into 2. thus, ans = PHN
6bii) Angle BDC = 100-58.6 = 41.4
(BC)^2 = 182 + 302 - 2*18*30*cos 41.4 = 1224 - 810.11 = 414
BC =
biii) area of triangle ADB + BDC = 0.5 * 26 *30sin'41.4' + 0.5 *18* 30sin'41.4' = 436
7dii) so the new co-ordinates are
(8,6) --> (4,3)
(10,12)--> (5,6)
(6,10) --> (3,5)
plot them.
if u observe carefully, ull see dii) it is an enlargement of factor 0.5 and the center (0,0)
e) check the diagram
8b) 3/(2x-1) + 1
(2+2x)(2x-1)
c) y = 3/x +1
x=3/y + 1
x-1 = 3/y
xy -y = 3
y(x-1) = 3
y = 3/(x-1)
g-1(x) = 3/(x-1)
d) h(3) = 8
h(8) = 2^8 = 256
e) g(-24/7) = 0.125
h(x) = 0.125
2^x = 0.125
2^x = 2^(-3)
x = -3
9bv) 3^(n-1)
bvi) Sequence S - Sequence T = (n+1)^2 - 3^(n-1)
d) 3^(n-1) = 177147= 3^11
n-1 = 11
n= 12
------------------------------------------------------------
Post by: pap19 on May 18, 2010, 11:32:55 am
Post by: Ghost Of Highbury on May 18, 2010, 11:37:29 am
pls tell me how to do oct/nov paper 4 maths 2000 question #2 c part......
gotta wait dear..hav to complete 15 more questions in toto..
Post by: pap19 on May 18, 2010, 11:46:50 am
Post by: Malak on May 18, 2010, 12:03:32 pm
thx
Post by: Vin on May 18, 2010, 12:17:13 pm
How do u find Meadian? From the table??
thx
which one r u talkin abt ??
Post by: Ghost Of Highbury on May 18, 2010, 12:18:19 pm
pls tell me how to do oct/nov paper 4 maths 2000 question #2 c part......
upload the pic/paper..
Post by: Vin on May 18, 2010, 12:24:23 pm
here Aadi i know how to find the answer but i cant find the equation for it .. i 'll try once again ..
Post by: Malak on May 18, 2010, 12:35:04 pm
which one r u talkin abt ??In General...I jst wanna knw the basic method for finding it.. :)
And also...How do u find the invariant line for shear and strech..is it always x or y axis? ???
Post by: Ghost Of Highbury on May 18, 2010, 12:37:01 pm
pls tell me how o do question 2 part b n c and full question 3 of maths paper 4 oct/nov 2000
gotta find the determinant first = 5t^2 -6t
thus the inverse...
(5t/5t^2-6t -6/5t^2-6t) = (-5t 6)
(-t/5t^2-6t t/5t^2-6t) (t -t)
that means 5t/5t^2-6t = -5t
therefore, 5t^2-6t = -1
-5t^2 + 6t = 1
-5t^2 + 6t -1 = 0
t = 1/5,1
Post by: mdwael on May 18, 2010, 12:41:34 pm
Post by: big mac on May 18, 2010, 12:49:56 pm
Post by: diva_sparkles on May 18, 2010, 12:54:00 pm
How do u find Meadian? From the table??
thx
if its an odd no thn use n+1/2
if its an even no thn n/2 and n+1/2
Post by: Ghost Of Highbury on May 18, 2010, 01:05:47 pm
gotta find the determinant first = 5t^2 -6t
thus the inverse...
(5t/5t^2-6t -6/5t^2-6t) = (-5t 6)
(-t/5t^2-6t t/5t^2-6t) (t -t)
that means 5t/5t^2-6t = -5t
therefore, 5t^2-6t = -1
-5t^2 + 6t = 1
-5t^2 + 6t -1 = 0
t = 1/5,1
2c) multiply the matrices --> (x^2 + 10) = kx
x^2 + 10 - kx =0
x^2 + 8x + 10 = 0
compare the co-efficients of x..
-k = 8
k = -8
Post by: Vin on May 18, 2010, 01:06:01 pm
Anybody knows where to find the markscheme for paper 4 maths summer year 2000?
Post by: Vin on May 18, 2010, 01:06:55 pm
gotta find the determinant first = 5t^2 -6t
thus the inverse...
(5t/5t^2-6t -6/5t^2-6t) = (-5t 6)
(-t/5t^2-6t t/5t^2-6t) (t -t)
that means 5t/5t^2-6t = -5t
therefore, 5t^2-6t = -1
-5t^2 + 6t = 1
-5t^2 + 6t -1 = 0
t = 1/5,1
thanks stupid me !! did a silly mistake .. +rep
Post by: M'i'D'o on May 18, 2010, 01:21:20 pm
plz reply
thanksss
Post by: Kojoudeh95 on May 18, 2010, 01:30:54 pm
Post by: Vin on May 18, 2010, 02:33:46 pm
Can some plz help :S how do u do questin 6 a) i) in paper 4 oct/nov 2007........i just want to no how to draw it...i no how to construct everything but plz tell me the steps for this :D
Ya so for this one u gotta take the scale as 1cm is 200cm so 1.8 cm 2.6 cm 3cm etc
Post by: Vin on May 18, 2010, 02:40:58 pm
hey everyone..... can anybody explain to me the linear programming... what to shade in a inquality like Y = or < 2x+3 for example ??
plz reply
thanksss
Shade th region where
y =<2x +3
y =<3
x =<5
Post by: Adzel on May 18, 2010, 02:56:34 pm
Post by: mdwael on May 18, 2010, 03:00:22 pm
Post by: Fastal on May 18, 2010, 03:04:30 pm
hey I got a really hard confusing question in summer 2000 paper its page 7 (a) part were you have to draw an accuarate histogram. it says "use a scale of 2cm to represent 5 grams on the horizontal axis, and an area of 1 square centimeter to represent 5 eggs" how do I do that? can someone upload a picture of the histogram if he/she has done it before? Thanks for helping :)
woah i hhave the same question
Post by: Ghost Of Highbury on May 18, 2010, 04:02:38 pm
first get this clear...how the x-axis will be arranged..
5 grams = 2 cm
1) 35<=m<40 = 5 grams = 2cm
2) 40<=m<50 = 10grams = 4cm
3) 50<=m<60 = 10 grams = 4cm
4) 60<=m<75 = 15 grams = 6cm
5) 75<=m<80 = 5 grams = 2cm
now..1cm^2 = 5 eggs.
for the 1st set i.e 35<=m<40...say the height of the rectangle = h
thus, the area of the rectangle = the frequency = 2cm*h cm = 2h cm^2
1cm^2 = 5 eggs
2h cm^2 = 5*2h = 10h eggs. (area)
now the area = frequency
10h eggs = 20 (f)
h = 2cm
thus, for the first rectangle, the height is 2cm, and the width - 2cm (5 grams class width)
do the same for the rest..
2) class width = 10 grams = 4cm
height = h
area = 4hcm^2
1cm^2 = 5 eggs
4h cm^2 = 20h
20h = frequency = 60
h= 3cm
3) class width = 10grams = 4cm
area = 4hcm^2
1cm^2 = 5 eggs
4h cm^2 = 20h eggs
20h = 200
h = 10cm
4) cw = 15 grams = 6cm
area = 6hcm^2
6h*5 = 30h eggs
30h = 180
h = 6cm
5) cw = 5 grams = 2cm
area = 2hcm^2
2h*5 = 10h eggs
10h = 40
h = 4cm.
Post by: Ghost Of Highbury on May 18, 2010, 04:04:39 pm
O/N 2004 04 Q3 part (b) and (c) + explaination.....please :)
b) Water out from the pipe = 1.6cm^2 * 14 cm/sec = 22.4 cm^3 /sec
Volume of the tank - 552920.3071 cm^3
22.4cm^3 = 1 second
552920.3071 = 52920.3071/22.4 = 24683.94228 seconds = 6 hours 51 minutes
c) 1m = 100cm
1m^2 = 10000cm^2
70m^2 = 700000cm^2
552920.3071cm^3/700000cm^2 = 0.789886153 cm = 7.9mm
Nearest mm = 8mm
Post by: Adzel on May 18, 2010, 04:14:05 pm
Post by: ksitna on May 18, 2010, 04:16:02 pm
Factorise completely m^4n ? 16n^5.
Post by: Adzel on May 18, 2010, 04:19:51 pm
Post by: Vin on May 18, 2010, 04:21:03 pm
O/N 2004 04 Q3 part (b) and (c) + explaination.....please :)
this one is quite easy ..
3 a) V= pi * r2 *h
= pi * 402 *110
=552920.3
=553000 cm3
b) in this one water comes out at the speed of 14 cm/s through 1.6 cm2
so 14 * 1.6 volume of water comes out if the pipe
= 22.4 cm3/sec
meaning 22.4 cubic cms of water will pass every sec .. so how long does it take to fill the cylinder ..
so time taken would be
553000
--------
22.4
=24687.5 sec / 60
= 411.45833333 mins /60
= 6.8576389 hrs
=6 hrs 51 mins
c) in this one the SA is given .. so ..
SA in mm = 70 * 100 * 100
= 700000 mm2
vol = SA * h
553000 = 700000 * h
h = 0.79 cm
= 7.9 mm
;)
Post by: $H00t!N& $t@r on May 18, 2010, 04:25:21 pm
Post by: Vin on May 18, 2010, 04:27:30 pm
need help with p4 O/N 2005 Q7c(ii)
ok gimme 2 mins
volume of pool = 1512 m3 * 100 *100 *100
=1512000000 cm3
volume of pipe = 6870 cm3
=1512000000 cm3
-----------------
6870 cm3
=ans / 60(min) * 60(hrs) *24
=2.5473 days
=2 days 13 hrs
sorry net prob. !!
Post by: Adzel on May 18, 2010, 04:31:13 pm
same paper VIN Q4 part (f), Q5 part (b) + explaination...please :)
Post by: Vin on May 18, 2010, 04:48:23 pm
imma hav my dinner till then try
https://studentforums.biz/index.php/topic,5575.msg167872.html#msg167872
aadi's made our lives easier ..
Post by: $H00t!N& $t@r on May 18, 2010, 04:48:41 pm
Post by: Vin on May 18, 2010, 04:50:08 pm
yea sorry .. typo thanks =)
Post by: Ghost Of Highbury on May 18, 2010, 04:57:48 pm
same paper A@di Q4 part (f), Q5 part (b) + explaination...please :)
4f) check the link given by VN to see the list. check the transformation matrix for stretch with y-axis invariant
(2 2) * (1.5 0) = (3 2)
(5 2) (0 1) (7.5 2)
(2,2) --> (3,2)
(5,2) --> (7.5,2)
do the same with the last set of co-ordinate ..to get the image co-ordinates as (7.5,4)
ii) v already hav used it
(1.5 0)
(0 1)
5b)i) p is AO (check diagram)
ACO is 51 degree, alternate interior to NAC.
70/sin 90 = p/sin51
p = 70sin51 = 54.4
bii)
q^2 = 70^2 - 54.4^2 = 1940.64
q = 44.1
Post by: thenewkid™ on May 18, 2010, 05:02:30 pm
Thanks
Post by: saleemsamer on May 18, 2010, 05:05:46 pm
Post by: Ghost Of Highbury on May 18, 2010, 05:12:47 pm
can any1 pls help me wid may/june 2007 p4 q 3b (i)
Thanks
as they both are similar triangles, their respective sides are in proportion
y/y+2 = (2y-1)/(y+1)
simplify this equation to get
y^2 - 4y - 2 = 0
Post by: mdwael on May 18, 2010, 05:19:33 pm
By the way the MS says its "end of interval is 60, 20+40+200" ??? ???
Post by: $H00t!N& $t@r on May 18, 2010, 05:20:26 pm
ok gimme 2 mins
volume of pool = 1512 m3 * 100 *100 *100
=1512000000 cm3
volume of pipe = 6870 cm3
=1512000000 cm3
-----------------
6870 cm3
=ans / 60(min) * 60(hrs) *24
=24.5473 days
=24 days 13 hrs
sorry net prob. !!
um.. i still dont get it... can u elaborate a bit more. By the way the ans in the ms is 2 days 13 hours
Post by: thenewkid™ on May 18, 2010, 05:21:27 pm
as they both are similar triangles, their respective sides are in proportionooooooooooooo now i see. Thanks
y/y+2 = (2y-1)/(y+1)
simplify this equation to get
y^2 - 4y - 2 = 0
Post by: djwaqar* on May 18, 2010, 05:23:09 pm
How to solve this question
i have been tryiing to solve it from the past 20 mints
Post by: ksitna on May 18, 2010, 05:24:15 pm
i dont get how they did this
Factorise completely m^4n ? 16n^5.
help plz!
Post by: Ghost Of Highbury on May 18, 2010, 05:25:12 pm
help plz!
plz check the question before u post it...wat does the "?" mean...
Post by: NidZ- Hero on May 18, 2010, 05:29:08 pm
Question2.C may/june 2006 paper4hey same doubt here de last part is cofusin can any1 help wid this
How to solve this question
i have been tryiing to solve it from the past 20 mints
thanku
Post by: saleemsamer on May 18, 2010, 05:29:43 pm
can some1 plz explain jun 2007 p4 q 2f and 4 c-e :)
Post by: mdwael on May 18, 2010, 05:34:29 pm
They may sound a stupid question but to me its not. Its this question in summer 2000 paper 4 page 7 c(i) part it says "explain why the point (60,280) is on the curve?" this is the first time I face this kind of question, I was hoping someone could explain it to me
By the way the MS says its "end of interval is 60, 20+40+200" ??? ???
Please answer my question, before I start headbutting the walls >:( :P
Post by: thenewkid™ on May 18, 2010, 05:38:06 pm
Quote
Question2.C may/june 2006 paper4
How to solve this question
i have been tryiing to solve it from the past 20 mints
for part c multiply the area of the cross-section by 40
as for the surface area calculate the area of each of its faces and add them together
Post by: Vin on May 18, 2010, 05:38:16 pm
um.. i still dont get it... can u elaborate a bit more. By the way the ans in the ms is 2 days 13 hours
sorry im on a real hurry doin french maths together !! im sorry if u see again the working is right .. so wat didnt u understand ??
When the pool is emptied, the water flows through a cylindrical pipe of radius 12.5 cm.
so the volume of pool is emptied i.e
volume of pool = 1512 m3 * 100 *100 *100
=1512000000 cm3
The water flows along this pipe at a rate of 14 centimetres per second.
so the area of pipe is pi * 12.52 =490.874 cm2
flows at 14cm/s so volume per second = 490.874 cm2 * 14cm/s
= 6870 cm3
Calculate the time taken to empty the pool.
Give your answer in days and hours, correct to the nearest hour.
volume emptying
---------------
rate of vol emptying
=1512000000 cm3
-----------------
6870 cm3/sec
=ans / 60(min) * 60(hrs) *24
=2.5473 days
=2 days 13 hrs
Post by: Ghost Of Highbury on May 18, 2010, 05:41:42 pm
hey same doubt here de last part is cofusin can any1 help wid this
thanku
look at diagram 2
the shape ABO has an area of = 90/360 * 144pi = 113
area of the horizontal rectangle = (12+10=22) * (18-12=6) = 132
area of the BOCG = 12*10 = 120
total = 365
365*40 = 14600cm^3
Post by: ksitna on May 18, 2010, 05:41:57 pm
plz check the question before u post it...wat does the "?" mean...
oh sorry
its minus
Post by: Vin on May 18, 2010, 05:42:08 pm
tht gives the area of "rectangle" BCAE ( u visualise it by 'removing' tht part from the fig. )
Post by: saleemsamer on May 18, 2010, 05:42:31 pm
can some1 plz explain jun 2007 p4 q 2f and 4 c-eplz help ???
Post by: Ghost Of Highbury on May 18, 2010, 05:44:00 pm
Post by: saleemsamer on May 18, 2010, 05:46:09 pm
@saleesameer - hold on..answering urs now..Thank You its just tht im abit stressed :-[
Post by: NidZ- Hero on May 18, 2010, 05:57:41 pm
thanz a Lot a big confusion :D
Post by: Ghost Of Highbury on May 18, 2010, 05:58:42 pm
can some1 plz explain jun 2007 p4 q 2f and 4 c-e :)
take 2 sets of c-ordinates (2,1) (3,3)
(1 0) * (2 3) = (2 3)
(-1 1) (1 3) (-1 0)
do the same with the other co-ordinate
(2,1) --> (2,-1)
(3,3) --> (3,0)
(5,1) --> (5,-4)
ii) https://studentforums.biz/index.php/topic,5575.msg167872.html#msg167872
check that..
if u see carefully, its the matrix which represents..shear of shear factor = -1 and y invariant.
iii) inverse of the transformation matrix which mapped ABC to A3B3C3
that is inverse of (1 0) = (1 0)
(-1 1) (1 1)
4c) this means that find two values for 'y' for which there are 2 values of x for each of them
for this u have to use the graph, check the diagram..
put straight lines where u think the line will intersect the graph twice..
(red lines)
ull notice, that wen y = 3...x has 2 values..
also, wen y = -9, x has two values
4e) f(x) + x -1 =0
as f(x)=y
y+x-1 = 0
y = 1-x
draw the line y = 1-x in the graph
eii) it cuts the graph at 3 points...meaning it has 3 solutions
Post by: saleemsamer on May 18, 2010, 06:02:53 pm
take 2 sets of c-ordinates (2,1) (3,3)
(1 0) * (2 3) = (2 3)
(-1 1) (1 3) (-1 0)
do the same with the other co-ordinate
(2,1) --> (2,-1)
(3,3) --> (3,0)
(5,1) --> (5,-4)
ii) https://studentforums.biz/index.php/topic,5575.msg167872.html#msg167872
check that..
if u see carefully, its the matrix which represents..shear of shear factor = -1 and y invariant.
iii) inverse of the transformation matrix which mapped ABC to A3B3C3
that is inverse of (1 0) = (1 0)
(-1 1) (1 1)
Thank You but wat abt 4
Post by: Vin on May 18, 2010, 06:03:16 pm
oh sorry
its minus
wats the answer ?? did u type the correct ques =P .. i think i got it ..
Post by: Vin on May 18, 2010, 06:04:05 pm
thanz a Lot a big confusion :D
which one u talkin abt ?? u didnt get it ??
Post by: Ghost Of Highbury on May 18, 2010, 06:07:08 pm
Thank You but wat abt 4
check again.
@ksitna -
check the question again.
Post by: NidZ- Hero on May 18, 2010, 06:12:40 pm
which one u talkin abt ?? u didnt get it ??2006 m/j 2 d its 4 marks
Post by: saleemsamer on May 18, 2010, 06:13:11 pm
check again.Thank You :)
@ksitna -
check the question again.
Post by: Kojoudeh95 on May 18, 2010, 06:16:48 pm
2) stretch description
PLZ and thx :D
Post by: Ghost Of Highbury on May 18, 2010, 06:20:26 pm
Hi guys,
I'm new here... Been reading these posts for a couple days now, but just didn't have any personal questions. UNTIL NOW.
I have a problem with a function graph - I need help with O/N 2001 Paper 4, question 6a.) iii.
How do you use a graph to find an inverse function?
If anyone could explain, I'd REALLY appreciate it - Paper tomorrow!!! Thanks :)
(paper + mark scheme attached)
ok look
first u have to understand wats the relation b/w g(x) and g-1(x)
e.g : say g(x) = x+2
thus, g(2) = 4
g-1(x) = x-2
now, if u apply 4 in g-1(x) , u will get 2
another e.g - g(4) = 6, apply 6 in g-1(x) and u get 4
same thing here...they've asked g-1(-0.5)
meaning, wat do u have to apply in g(x) to get -0.5 ?? meaning g(x) = -0.5, y = g(x), thus, y = -0.5...draw this line and see where it intersects y = g(x)
from the graph , it intersects at x = -1
this means that if u apply -1 in g(x) u get -0.5
thus if u apply -0.5 in g-1(x) u'll get -1.
:D
Post by: Vin on May 18, 2010, 06:23:20 pm
2006 m/j 2 d its 4 marks
Area of CBAED = 365 cm2 u got in b)
multiply by 2 .. two sides
= 730 cm2
area of 'yellow' part .. u kno the perimeter so*40 add u get ..
imagine u cut open the yellow part ... it forms a triangle
Post by: $H00t!N& $t@r on May 18, 2010, 06:23:46 pm
oh im really sry for disturbing you. sry i made you do all that. i completely understand it now. thx a zillion!!! gdluck with both, french and maths!
Post by: Ghost Of Highbury on May 18, 2010, 06:35:12 pm
Also having trouble with probability - O/N 2002 Paper 4 Q4 a. iii.) and b. iv. and v.)
:'(
Thanks in advance to anyone who can help me out
4aiii) probability that the no. is shaded : 4/10
prob. that the no. is even : 5/10
4/10 + 5/10 = 9/10
however, it cant be 2 or 4, because they're shaded and even...prob. of getting 2 or 4 = 2/10
9/10 - 2/10 = 7/10
biv) possibilities : (1,1) (2,1) (1,2)
(1,1) = 1/10 * 1/10 = 1/100
(2,1) = 1/100
(1,2) = 1/100
1/100 + 1/100 + 1/100 = 0.03
Post by: Ghost Of Highbury on May 18, 2010, 06:43:55 pm
thanks so much! i hate that feeling when i realize i was making stupid mistakes the entire time and the question is actually so much easier than i originally thought... <kicks self>
no problem..
Post by: Airhead on May 18, 2010, 06:48:19 pm
Post by: The Golden Girl =D on May 18, 2010, 06:50:45 pm
gd luck everyone :D
Post by: Ghost Of Highbury on May 18, 2010, 07:02:06 pm
Can anyone help me out with M/J 2008, question 4 part c? It's a little confusing :P
height = frequency/n
9 = 30/n
n = 3.33.
class width = n* standard width
10 = 3.33.. * sw
sw = 3
---
h = sw * f/cw
for 0<h<=30
h = 3 * 82/30 = 8.2
do the same for the rest...
Post by: aangel42 on May 18, 2010, 07:06:44 pm
Post by: Airhead on May 18, 2010, 07:11:12 pm
Post by: princess12 on May 18, 2010, 07:12:15 pm
reply me fast urgently plaese ??? ??? ??? ??? ??? ???
Post by: CatAly$t on May 18, 2010, 07:12:59 pm
i need to know: how to know the scale factor?
how to know which axis is the invariant?
thanks.............
Post by: Ghost Of Highbury on May 18, 2010, 07:13:17 pm
If anyone has the time: June 2003 Paper 4 Q7 b. ii.) ????
CF = 2a-2b
CF/2 = a-b
CF/2 = CX
CX = a-b
CX is parallel to AB
|AB| = |OA| .. ( |AB| means length of AB)
OA = a
|AB| = a = 5
Post by: princess12 on May 18, 2010, 07:18:59 pm
??? ??? ??? ??? ??? ??? ??? ??? ??? ???
Post by: Dibss on May 18, 2010, 07:19:24 pm
iv) a student who likes football is selected at random. what is the probability that this student likes basketball?
i know it's a simple qs, but please answer since my answer was different from my teacher's and since i don't know if it's from a past paper i can't use a mark scheme to check :|
Post by: Vin on May 18, 2010, 07:19:52 pm
can somebody tell me about shear and stretch?? m really confused.... :-\
i need to know: how to know the scale factor?
how to know which axis is the invariant?
thanks.............
all taken from the forum ..
Post by: Shazizzzle on May 18, 2010, 07:21:27 pm
Post by: Ghost Of Highbury on May 18, 2010, 07:21:36 pm
can any 1 explain me oct 2003 q 1 (b) all ??? ??? ??? ??? ??? ??? ???
reply me fast urgently plaese ??? ??? ??? ??? ??? ???
ans 1b) 144 adults, 96 children
bi) 1/3 * 96 = 32 children
bii) 37.5/100 * 144 = 54 adults
biii) 144-54 = 90
90 + 20 = 110 adults
biv) 96-32 = 64 children still left
110 adults already in..
110 + 64 = 174
200 - 174 = 26..
Post by: Vin on May 18, 2010, 07:22:51 pm
Q- 24 students in a class asked whether they like football or basket ball.
iv) a student who likes football is selected at random. what is the probability that this student likes basketball?
i know it's a simple qs, but please answer since my answer was different from my teacher's and since i don't know if it's from a past paper i can't use a mark scheme to check :|
whoa insufficient data !!
Post by: Ghost Of Highbury on May 18, 2010, 07:23:43 pm
Q- 24 students in a class asked whether they like football or basket ball.
iv) a student who likes football is selected at random. what is the probability that this student likes basketball?
i know it's a simple qs, but please answer since my answer was different from my teacher's and since i don't know if it's from a past paper i can't use a mark scheme to check :|
Check the question, any other details given?? For e.g how many like only basket ball, or how many like only football etc??
Post by: Syed Kazim on May 18, 2010, 07:25:31 pm
Q- 24 students in a class asked whether they like football or basket ball.
iv) a student who likes football is selected at random. what is the probability that this student likes basketball?
i know it's a simple qs, but please answer since my answer was different from my teacher's and since i don't know if it's from a past paper i can't use a mark scheme to check :|
The question is from O/N/05. Question 4.
The answer written above is incorrect. The correct answer is 12/19. Read this (https://studentforums.biz/index.php/topic,7086.msg209870.html#msg209870) post to know more.
Post by: Vin on May 18, 2010, 07:26:17 pm
Check the question, any other details given?? For e.g how many like only basket ball, or how many like only football etc??
DUDE A LOT OF HARD WORK U R DOIN !! STANDING OVATION FROM ME !! :D :D
Post by: aangel42 on May 18, 2010, 07:27:09 pm
There's no other way?
Post by: Vin on May 18, 2010, 07:28:02 pm
Can a vector only be "equal" to another one if it is parallel to it?
There's no other way?
if in same direction and same size ..
Post by: Ghost Of Highbury on May 18, 2010, 07:31:48 pm
@aangel42 - if u r referring to the previous question, they're equal because the question says they are "EQUILATERAL TRIANGLES"
Post by: $H00t!N& $t@r on May 18, 2010, 07:33:40 pm
Q- 24 students in a class asked whether they like football or basket ball.u sure that question is complete? cz i dnt think theres any way of solving it with the info given...
iv) a student who likes football is selected at random. what is the probability that this student likes basketball?
i know it's a simple qs, but please answer since my answer was different from my teacher's and since i don't know if it's from a past paper i can't use a mark scheme to check :|
Post by: Vin on May 18, 2010, 07:35:12 pm
The question is from O/N/05. Question 4.
@Dibss
u want the solution ??
Post by: Ghost Of Highbury on May 18, 2010, 07:35:54 pm
its not 14/24..
its 12/19
because..if the player likes basketball AND football he belongs to the group of 12..
however they say he likes football..first..so the larger group is 19
therefore, 12/19 .
Post by: princess12 on May 18, 2010, 07:35:58 pm
Post by: Ghost Of Highbury on May 18, 2010, 07:38:08 pm
by the way thanks adi
Ur welcome..
Post by: The Golden Girl =D on May 18, 2010, 07:39:15 pm
Post by: Vin on May 18, 2010, 07:45:54 pm
yay first !! =P
Post by: Ghost Of Highbury on May 18, 2010, 07:47:39 pm
yay first !! =P
lol, thanks
Post by: Syed Kazim on May 18, 2010, 07:49:19 pm
well, if thats the question..
its not 14/24..
its 12/19
because..if the player likes basketball AND football he belongs to the group of 12..
however they say he likes football..first..so the larger group is 19
therefore, 12/19 .
Oops, I wrote the solution to the question before the one he asked. Sorry.
He asked 4a)vi and I answered 4a)v. :-[
Post by: The Golden Girl =D on May 18, 2010, 07:49:44 pm
yay first !! =Pthx bro ..but umm i dn't get how u got 98?!?!?! ..plz do explain srry :-[ :-[
Post by: Vin on May 18, 2010, 07:50:09 pm
P.S im not showing off =P
Post by: Ghost Of Highbury on May 18, 2010, 07:50:32 pm
lol, thanks
60+13+36 = 109
180-109 = 71
360-71 = 289
easier
Post by: K_M on May 18, 2010, 07:54:23 pm
Post by: The Golden Girl =D on May 18, 2010, 07:54:53 pm
60+13+36 = 109
180-109 = 71
360-71 = 289
easier
thx dude
Post by: princess12 on May 18, 2010, 07:55:11 pm
can u explain me oct 2003 p 4 q 5 ??? ??? ??? ??? ??? ??? ??? ??? ???
Post by: Ghost Of Highbury on May 18, 2010, 07:57:08 pm
can u explain aadi to me oct 2003 p 4 q 5
ans 5a) i) 2/10 (total 2 cards with D)
5aii) 4/10 (4 reds)
aiii) card is red: 4/10
D on the card : 2/10
6/10 however, it cant be the Red D card because its "or" ... so that is 6/10 - 1/10 = 5/10
aiv) theres only 1 card of that type. thus 1/10
av) no such card. 0
Post by: Vin on May 18, 2010, 07:57:25 pm
thx dude
yea actually i did it the other way round .. im bad at mind calculations ..
Post by: Shazizzzle on May 18, 2010, 07:59:42 pm
can u explain aadi to me oct 2003 p 4 q 5
Q5.
(a)
i) Two cards have D, out of 10, so 2/10 = 0.2
ii)4 cards are red, out of the 10, so 4/10 = 0.4
iii)Remember Probability of A OR B= P(A) + P(B) - P(A intersection B)
Here, Prob. of being red: 4/10. Prob. of being D: 2/10. Prob. of being Red AND (intersection) D at the same time, is 1/10 (as only ONE card Is both red AND has D)
So prob of red + prob of D - prob of Red and D = 4/10 + 2/10 - 1/10 = 5/10 = 0.5
iv) Prob of red: 4/10 prob the card is D OUT of the red: 1/4
So, prob red X prob of D OUT OF Red = 4/10 X 1/4 = 4/40 = 0.1
v) There is NO CARD THAT IS RED with AN N ON IT. So, ZERO. 0.
Post by: princess12 on May 18, 2010, 07:59:55 pm
Post by: princess12 on May 18, 2010, 08:01:31 pm
good luck for maths paper 4 to all
Post by: YNWA on May 18, 2010, 08:03:14 pm
Oct/Nov 2001 Q.6
(b) (i) (ii) (iii) and (d)
Post by: Ghost Of Highbury on May 18, 2010, 08:04:14 pm
what about part b aadi in same question
sorry, didnt see that...
bi) 2/10 (for the first D) * 1/9 (1 because theres only 1 D left, and 9, because thats the total no. cards left) = 1/45
bii) 3/10 * 2/9 = 1/15
iii) can be A or D.. -> both A - 1/15 , both D - 1/45
1/15 + 1/45 = 4/45
biv) 1-41/45 = 4/45
Post by: Shazizzzle on May 18, 2010, 08:04:53 pm
Graphs of functions again. I can't seem to find the markscheme for this one, could someone give me the answers so i can check them?
Oct/Nov 2001 Q.6
(b) (i) (ii) (iii) and (d)
http://www.scribd.com/doc/3182918/Math-Answers-P2-P4-1993-2003
Post by: badass on May 18, 2010, 08:14:45 pm
Post by: Ghost Of Highbury on May 18, 2010, 08:15:03 pm
minor typo - b. iv.) is 41/45
Thanks..
Post by: Ghost Of Highbury on May 18, 2010, 08:16:14 pm
does anyone have a shear and stretch question to practice. haven't seen any stretches and don't really understand them
june 2007 , queation 2f..
Post by: mdwael on May 18, 2010, 08:22:25 pm
Post by: CatAly$t on May 18, 2010, 08:24:05 pm
all taken from the forum ..
thanks!!!u saved my life.... :D
Post by: Ghost Of Highbury on May 18, 2010, 08:28:32 pm
1,2,4,7,11,16 whats the nth term for this kindof sequence? gradually adding by increasing numbers +1 +2 +3 but how do you find the nth term?
'Changing Difference' Sequences
The general term for term number 'n' , common diff. 'd' , first term 'a' and difference change 'c'is:
a+d(n-1)+c/2(n-1)(n-2)
a = 1
d = 1 (first difference)
1 2 4 7 11
1 2 3 4
1 1 1
c = 1 (final difference)
a+d(n-1)+c/2(n-1)(n-2)
1+(n-1)+0.5(n-1)(n-2)
1+n-1+0.5(n^2 -3n + 2)
1+n-1+0.5n^2 - 1.5n + 1
0.5n^2 -0.5n + 1.
Post by: M'i'D'o on May 18, 2010, 08:33:09 pm
Inequalities... I HATE IT.. plzz heeelp i'm dying for it......
Post by: Shazizzzle on May 18, 2010, 08:37:12 pm
Anyway, I'm having an offline revision today, so later guys.
And BEST OF LUCK! :D
Post by: Candela on May 18, 2010, 08:41:34 pm
wat other topics r u guys expecting?!
Post by: Shazizzzle on May 18, 2010, 08:43:57 pm
i think probability is a must! :S
wat other topics r u guys expecting?!
The examiner is fond of investigating questions, so
1. Probability
2. Sequence
Both are for sure.
As transformations and graphs are considered 'easy' and of 'free marks' by the examiner, and as they appeared in N09, I can bet there won't be any this session.
Umm, statistcs.
Also, angle properties!
And trignometry!
And, ofcourse, the first question, relating to percentages.
Post by: $H00t!N& $t@r on May 18, 2010, 08:45:30 pm
Post by: ~HyDrOgEn~ on May 18, 2010, 08:49:10 pm
Post by: princess12 on May 18, 2010, 08:49:42 pm
Post by: Candela on May 18, 2010, 08:49:50 pm
The examiner is fond of investigating questions, so
1. Probability
2. Sequence
Both are for sure.
As transformations and graphs are considered 'easy' and of 'free marks' by the examiner, and as they appeared in N09, I can bet there won't be any this session.
Umm, statistcs.
Also, angle properties!
And trignometry!
And, ofcourse, the first question, relating to percentages.
can u tell me all the formulas for sequences!
i jus know -- > a+ (n-1) d
Post by: princess12 on May 18, 2010, 08:50:45 pm
WHAT IS A N D
Post by: $H00t!N& $t@r on May 18, 2010, 08:53:26 pm
HEY SHOOTING STAR WE SHOULD THE PASTPAPER FROM 2003the thing is that ive done them all and im doing the ones before that for further practice. so... can you help me with the question i asked?
Post by: NidZ- Hero on May 18, 2010, 08:56:12 pm
Post by: ~HyDrOgEn~ on May 18, 2010, 09:02:24 pm
No One is Helping me WIth bearings. i feel bad
[/size]
Post by: Dr.virus007™ on May 18, 2010, 09:02:32 pm
Post by: Candela on May 18, 2010, 09:04:00 pm
a+ (n-1) da- the first term in d sequence.
WHAT IS A N D
n- nth term
d- the difference btween the terms!
i dont knw the other formulae for sequences?!anyone?!
Post by: princess12 on May 18, 2010, 09:10:53 pm
??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? :'( :'( :'( :'( :'( :'( :'( :'( :'( ??? ??? ??? ??? ??? ??? ??? ??? :'( :'( :'( :'( :'( :'(
Post by: Shazizzzle on May 18, 2010, 09:11:37 pm
can any 1 explain us the bearing in briefly please
fast urgent please
Suppose, bearing A from B.
A FROM B
So, at point B, you draw a north.
The angle from the North of B, in between that north and line joining B to A, is the bearing.
The bearing is always taken from the north, in CLOCKWISE DIRECTION, and is always written in THREE DIGITS.
e.g 030 deg.
Post by: 6394 on May 18, 2010, 09:13:38 pm
a- the first term in d sequence.i need sequence formulas as wel
n- nth term
d- the difference btween the terms!
i dont knw the other formulae for sequences?!anyone?!
Thanks alot :) :D
Post by: NidZ- Hero on May 18, 2010, 09:14:39 pm
Post by: bulono on May 18, 2010, 09:15:50 pm
Post by: ivrytwr3 on May 18, 2010, 09:16:15 pm
Question 4 part c. "Use trigonmetry to calculate the length of BC".
I did:
7 (cos 55)
Which obvioulsy isn't right as that would mean the hym is the shortest side :(
Where have i gone wrong please?!
Thank You!
Post by: princess12 on May 18, 2010, 09:16:33 pm
i can not find in my pastpapers
Post by: ksitna on May 18, 2010, 09:18:55 pm
Can anybody plz solve the question 9 in nov 06 paper 4 and attach it for me...
Inequalities... I HATE IT.. plzz heeelp i'm dying for it......
right um the inequalities to start of with
so he works no more than 12 hours
if x was washing cars and y was repairing cycles
that means that when he does both it would take him max. 12 hours
so x+y<=12
for the second one
he spends at least 4 hours so it would be x>= 4
when u plot the points
if the equation was less than
u would shade the right side because it is more than etc.
then for the least u just follow on the graph
(4,4)
and for the most
(6,6)
if u need further explanation do tell :)
Post by: Vin on May 18, 2010, 09:19:13 pm
guys plz help me with p4 nov 1999 q10
for b) there is a way to draw 3 equal lines i knew it .. cant remember!! we dont hav it in the portion .. and also i dont think we hav the remaining .. dont bother urself solving old paper .. ;) i can give u the answer but it'll take time .. i cant even find the book were i hav all types of geometrical rules and stuff (for engineering not fo us) im sure nothing like this will come !! know locus n stuff ..
Post by: bulono on May 18, 2010, 09:19:32 pm
Post by: princess12 on May 18, 2010, 09:20:20 pm
Post by: ksitna on May 18, 2010, 09:20:51 pm
dn+(a-d)
a+(n-1)d+0.5(n-1)(n-2)c
Post by: ksitna on May 18, 2010, 09:21:35 pm
formulas
dn+(a-d)
a+(n-1)d+0.5(n-1)(n-2)c
right sorry
where c is the difference increase
Post by: Vin on May 18, 2010, 09:22:29 pm
i need sequence formulas as wel
Thanks alot :) :D
s= a + (n - 1) d
d = common difference lik 2, 2, 2, ..
a = first term of sequence
..
Post by: Malak on May 18, 2010, 09:23:31 pm
Post by: Vin on May 18, 2010, 09:24:22 pm
can any1 plz help me wid m/j 2001 q8c
i can not find in my pastpapers
i cant find the paper either ..
Post by: bulono on May 18, 2010, 09:24:42 pm
Post by: Saavya on May 18, 2010, 09:25:00 pm
Changing difference sequence formula
a + (n-1)d + 0.5(n-1)(n-2)C
Where -
a = the first term
d = the first difference
C = The difference increase.
an example of its use-
sequence: 3, 5, 9, 15, 24, ...
a + (n-1)d + 0.5(n-1)(n-2)C
3 + (n-1)2 + 0.5(n-1)(n-2)2
3 + 2n - 2 + n2 - 2n - n + 2
= 3 + n2 - n
Proof, by finding the 4th term:
3 + n2 - n
3 + 16 - 4
Post by: Vin on May 18, 2010, 09:25:06 pm
can anyone tell how to find the invariant line?
check the attachment ..
Post by: Dr.virus007™ on May 18, 2010, 09:25:43 pm
right sorry
where c is the difference increase
R these two diff. formulas! ! !..........when do v use the first 1....nd when is the 2nd used...!!
Post by: ksitna on May 18, 2010, 09:28:10 pm
well u have to count a certain point
like choose a point and the scale factor u would be given
so if scale factor was 2
and for example in stretch
count how far it is
then for the object
u count how far as well
and when u find a line that satisfies them like if the furthest one was 10
and the object was 5
then that would be the invariant line
hope u got it
Post by: princess12 on May 18, 2010, 09:28:54 pm
Post by: haris94 on May 18, 2010, 09:29:37 pm
URGWNT help needed M/J 2004 question 2 c
x2-x-3=6-x3/3
3x2-3x-9=18-x3
x2+3x2-3x-27=0
Post by: bulono on May 18, 2010, 09:30:13 pm
Post by: $H00t!N& $t@r on May 18, 2010, 09:30:24 pm
for b) there is a way to draw 3 equal lines i knew it .. cant remember!! we dont hav it in the portion .. and also i dont think we hav the remaining .. dont bother urself solving old paper .. ;) i can give u the answer but it'll take time .. i cant even find the book were i hav all types of geometrical rules and stuff (for engineering not fo us) im sure nothing like this will come !! know locus n stuff ..damn ur good!!! Thanks alot, nt just fr this question but generally! as in ur genius man! hats off!!
Post by: haris94 on May 18, 2010, 09:31:46 pm
help needed M/J 2004 question 2 c.....mine is 11 00 am GMT 3+
scroll up....same page
i hv written it
Post by: Vin on May 18, 2010, 09:32:53 pm
Could someone take a look at 0580/03 Oct/Nov 2009 Paper 3 core
Question 4 part c. "Use trigonometry to calculate the length of BC".
I did:
7 (cos 55)
Which obvioulsy isn't right as that would mean the hym is the shortest side :(
Where have i gone wrong please?!
Thank You!
Sin x = opposite
---------
hypotenuse
tan x = opposite
----------
adjacent
cos x = adjacent
---------
hypotenuse
check this website ..
http://www.mathsisfun.com/sine-cosine-tangent.html
regarding ur sum ..
use sine
sin x = opposite
---------
hypotenuse
angle is given, name unknown as z
sin 35 = 7/z
z = 7/sin 35
z = 12.2 cm
LEARN THE TRIGONOMETRY FUNCTIONS !!!
Post by: bulono on May 18, 2010, 09:34:56 pm
Post by: haris94 on May 18, 2010, 09:35:15 pm
Post by: bulono on May 18, 2010, 09:35:47 pm
Post by: bulono on May 18, 2010, 09:37:22 pm
Post by: Shazizzzle on May 18, 2010, 09:41:19 pm
Cos x = Base/Hyp. (Curly Brown Hair)
Tan x = Perp./Base (Through Proper Brushing)
Some people have, curly brown hair, through proper brushing. :P
And the perpendicular (opposite) of ANY angle, is the side opposite of the angle.
That automatically makes the other side which is NOT the hyp. the base.
So, The Base and Perpendicular may be different for different angles in a right angled triangle
Then, Sine Rule.
Sin A Sin B Sin C
----- = ------ = -------
A B C
Then, Cosine rule.
a^2 = b^2 + c^2 - 2bc X Cos A
b^2 = a^2 + c^2 - 2ac X Cos B
c^2 = a^2 + b^2 - 2ab X Cos C
OR, if angle is needed,
Cos A = b^2 + c^2 - a^2 / 2bc (Note, the angle to be found is A. So on top, the last one being -sed will be a^2 - And the two being added above, will be the ones multiplying with 2 below)
Post by: Vin on May 18, 2010, 09:41:28 pm
help needed M/J 2004 question 2 c.....mine is 11 00 am GMT 3+
f(x) = x2 - x - 3
g(x) = 6 - X3/3
x2 - x - 3 = 6 - x3/3
x2 - x - 3 = 18 - x3
---------
3
3x2 - 3x - 9 = 18 - x3
x3 + 3x2 - 3x - 9 - 18 = 0
x3 + 3x2 - 3x - 27 = 0
ii) find the intersection of these two graphs and write down the coordinates
..
Post by: princess12 on May 18, 2010, 09:41:35 pm
urgently reply fast please
:'( :'( :'( :'( :'( :'( :'( :'( :'( :'( :'( :'( :'( ??? ??? ??? ??? ??? ??? ??? ???
Post by: Vin on May 18, 2010, 09:42:05 pm
Some people have, curly brown hair, through proper brushing. :P
LOL XD
Post by: Shazizzzle on May 18, 2010, 09:45:29 pm
There is only one conclusion. There is no general hard-and-fast rule for probability. Sometimes you have to add, sometimes multiply, sometimes 1-(). It depends on the Question. And there is no explanation to why. So, basically, it's all screwed.
Post by: Vin on May 18, 2010, 09:46:17 pm
can any 1 tell me please may 2004 p4 q2 part a(1) only
urgently reply fast please
:'( :'( :'( :'( :'( :'( :'( :'( :'( :'( :'( :'( :'( ??? ??? ??? ??? ??? ??? ??? ???
dont cry princess =P
f(x) = x2 - x - 3
for p
=(-3)2 -(- 3) - 3
= 9 + 3 - 3
=9
substitute " x " in f(x) try
..
Post by: haris94 on May 18, 2010, 09:46:47 pm
can any 1 tell me please may 2004 p4 q2 part a(1) only
urgently reply fast please
:'( :'( :'( :'( :'( :'( :'( :'( :'( :'( :'( :'( :'( ??? ??? ??? ??? ??? ??? ??? ???
p=(-3)2-(-3)-3=9+3-3=9
q=(1)2-(1)-3=1-1-3=-3
r=(4)2-(4)-3=16-4-3=9
Post by: ksitna on May 18, 2010, 09:47:03 pm
Post by: bulono on May 18, 2010, 09:48:12 pm
Post by: haris94 on May 18, 2010, 09:49:17 pm
4, 12, 24, 40...........
how do u find the nth term?
Post by: ksitna on May 18, 2010, 09:50:19 pm
and in M/J 2005 Q 3 b how do i find the matrix....
well
u would use simultaneous equations
(ab) the matrix of x = the matrix of q
(cd) times
Post by: SoONa on May 18, 2010, 09:50:35 pm
thanks in advance .. wish every1 luck ;D
Post by: bulono on May 18, 2010, 09:51:44 pm
Post by: Vin on May 18, 2010, 09:52:49 pm
Okay, I know what dependent events and independent events are, but where do we add and where do we multiply.
There is only one conclusion. There is no general hard-and-fast rule for probability. Sometimes you have to add, sometimes multiply, sometimes 1-(). It depends on the Question. And there is no explanation to why. So, basically, it's all screwed.
Addition is where there in no "Second Chance" lik pick up a coloured ball keep it back and pick another ball
Multiplication is where there is "more than one change" pick up a ball note colour pick up another ball (without replacing) note .. here the numerator and denominator of the second chance will decrease by one as u hav one ball in hand
Subraction is basically a "shortcut" .. like 1-1/10 or something .. solve maj/june 2009 paper 4 prob. ques it has subtraction P.S there is always an alternative method to a subtraction dont understand .. solve jun 2009
Post by: bulono on May 18, 2010, 09:56:21 pm
hello ,,it would be awsome if anyone can show me the answer to october november 06 q 9 ..the 3 inequalities are y>=x so y-x>=0.....y+x<=12 as total time working is less than 12......x>=4 as he spends at least 4 hours cleaning cars
thanks in advance .. wish every1 luck ;D
Post by: ksitna on May 18, 2010, 09:56:41 pm
suppose a sequence is
4, 12, 24, 40...........
how do u find the nth term?
u would use this method
a+(n-1)d+0.5(n-1)(n-2)c
4+(n-1)4+0.5(n-1)(n-2)4
and good l luck simplifying :)
Post by: SoONa on May 18, 2010, 10:00:08 pm
the 3 inequalities are y>=x so y-x>=0.....y+x<=12 as total time working is less than 12......x>=4 as he spends at least 4 hours cleaning cars
hmm can u like take a screen shot of ur answer for the region and umm whts the answer for d 1 n 2 ... Thanks alottttt
Post by: bulono on May 18, 2010, 10:01:12 pm
Post by: Vin on May 18, 2010, 10:02:33 pm
and in M/J 2005 Q 3 b how do i find the matrix....
another doubt M/J 2005 Q 2 c......
answered ??
Post by: haris94 on May 18, 2010, 10:03:02 pm
u would use this method
a+(n-1)d+0.5(n-1)(n-2)c
4+(n-1)4+0.5(n-1)(n-2)4
and good l luck simplifying :)
ummm im still not getting the right answer ???
i got 2n2-2n+4
the answer is 2n2+2n
can u pls simplify and show me
thanx a million
Post by: ksitna on May 18, 2010, 10:03:31 pm
hmm can u like take a screen shot of ur answer for the region and umm whts the answer for d 1 n 2 ... Thanks alottttt
in d1 and 2
u nned the graph
u look at the points that are the least (4,4)
and the highest (6,6)
but first you have to make sure if it really is the highest and lowest
or u can solve it algebraically
VIN yes i think they are answered
Post by: Vin on May 18, 2010, 10:06:14 pm
ummm im still not getting the right answer ???
i got 2n2-2n+4
the answer is 2n2+2n
can u pls simplify and show me
thanx a million
dude im getting the same .. =\
Post by: Vin on May 18, 2010, 10:07:05 pm
VIN yes i think they are answered
i see u;ve answered them ..
Post by: haris94 on May 18, 2010, 10:07:33 pm
Post by: bulono on May 18, 2010, 10:08:08 pm
answered ??yup....
Post by: Vin on May 18, 2010, 10:11:31 pm
then i think the formula is wrong ??? ???
number 'n' , common diff. 'd' , first term 'a' and difference change 'c'is:
a+d(n-1)+c/2(n-1)(n-2)
try this wat was the sequence By the way ??
Post by: ksitna on May 18, 2010, 10:12:22 pm
ummm im still not getting the right answer ???
i got 2n2-2n+4
the answer is 2n2+2n
can u pls simplify and show me
thanx a million
okie
i hate simlifying so im sorry it took a while :/
i got the same thing as u so i must have done somat wrong but wait lemme check again.
Post by: haris94 on May 18, 2010, 10:13:21 pm
okie
i hate simlifying so im sorry it took a while :/
i got the same thing as u so i must have done somat wrong but wait lemme check again.
k Thanks
Post by: ksitna on May 18, 2010, 10:14:32 pm
i see u;ve answered them ..
lol sorry....
right and i have no idea what i did wrong VIN help!!!
Post by: haris94 on May 18, 2010, 10:15:11 pm
number 'n' , common diff. 'd' , first term 'a' and difference change 'c'is:
a+d(n-1)+c/2(n-1)(n-2)
try this wat was the sequence By the way ??
yea thats the formula i used
sequence is
4, 12, 24, 40...........
Post by: ksitna on May 18, 2010, 10:17:41 pm
Post by: ksitna on May 18, 2010, 10:20:01 pm
did i do it wrong?
Post by: Vin on May 18, 2010, 10:24:24 pm
i got 2n2+2n-4
did i do it wrong?
nop .. the sequence is wrong !! +@
wats the ans !!
Post by: SoONa on May 18, 2010, 10:26:03 pm
in d1 and 2
u nned the graph
u look at the points that are the least (4,4)
and the highest (6,6)
but first you have to make sure if it really is the highest and lowest
or u can solve it algebraically
VIN yes i think they are answered
yeah i got the points is the final answer 18 n 27??
Post by: haris94 on May 18, 2010, 10:26:33 pm
*jumps in joy* :P :P
umm no yours isnt right
this is what i did 4 12 24 40
8 12 16
a+(n-1)d+0.5(n-1)(n-2)c 4 4
ok so "a" will be 4 (first term)
"d" will be first difference, that is 8
"c" is second difference thats is 4
so substitute and u get 2n2+2n
Thanks a lot for the fromula ;D
Post by: the_grim_reaper on May 18, 2010, 10:27:33 pm
1
see 4+(n-1)8+---(n-1)(n-2)4
2
Cut 1/2 by 4 to make it 2.
so its 4+(8n-8)+(n-1)(n-2)2
now, 4-8+8n + (n^2-2n-n+2)2
no its -4+8n+ (n^2-3n+2)2
which is -4+8n +2n^s-6n+4
finally, 2n^2+8n-6n-4+4
which is 2n^2+2n+0= 2n^2 + 2n
By the way, the formula is correct......
Post by: princess12 on May 18, 2010, 10:29:04 pm
??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ???
urgently fast reply plaese ??? ??? ??? ??? ??? ??? ??? ???
Post by: Shazizzzle on May 18, 2010, 10:30:35 pm
Post by: haris94 on May 18, 2010, 10:32:18 pm
1,3,6,10 write next 4 sequence fast please ??? ??? ??? ??? ??? ??? ??? ??? ???
??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ???
urgently fast reply plaese ??? ??? ??? ??? ??? ??? ??? ???
+2 +3 +4 +5 +6 +7
1 3 6 10 15 21 28
and so on
Post by: Vin on May 18, 2010, 10:32:26 pm
2 3 4 5 6 7 8 (add these nos to previous ones)
1 1 (add 1 to 4)
Post by: ksitna on May 18, 2010, 10:33:36 pm
yeah i got the points is the final answer 18 n 27??
yes thts correct :D
Post by: princess12 on May 18, 2010, 10:34:40 pm
Post by: Vin on May 18, 2010, 10:35:29 pm
LOL we are the masters of sequences !!
Post by: the_grim_reaper on May 18, 2010, 10:35:41 pm
Quote
1,3,6,10 write next 4 sequence fast please
urgently fast reply plaese
it's .5n^2+.5n
Just use a+(n-1)d+1/2(n-1)(n-2)c
where a is the first term (1), d is the difference between the first and second term (2 here) and c is the second difference
1 3 6 10
2 3 4 (3-1), (6-3), (10-6) NOW
1 1 (3-2), (4-3)
Find the next terms by substitution ( n by 5, 6, 7, 8,9)
Post by: Vin on May 18, 2010, 10:36:49 pm
dude chill she hasnt asked for the nth term =P
Post by: princess12 on May 18, 2010, 10:37:10 pm
GOOD LUCK EVERY ONE FOR ALL SUBJECTS :D :D :D :D :D :D :D :D :D :D :D :D :D :D :D :D :D :D :D :D :D :D :D :D
[/size][/color]
Post by: haris94 on May 18, 2010, 10:37:31 pm
LOL we are the masters of sequences !!
oyea 8)
Post by: the_grim_reaper on May 18, 2010, 10:38:32 pm
Quote
dude chill she hasnt asked for the nth term =P
HAHAHAHAHAH sorry :D. TOo sleepy. Didn't read it properly. Anyway, it'll help her understand how to find it :D.
Post by: bulono on May 18, 2010, 10:39:09 pm
Post by: ksitna on May 18, 2010, 10:39:57 pm
oyea 8)
absolutely! not simplifying tho :/
and good night bulono :)
good luck for tomz
Post by: the_grim_reaper on May 18, 2010, 10:41:02 pm
Quote
No, salooo!
Houn saloo??? hahaha I'll see you in the morning :P.
Post by: dsiddiqi11 on May 18, 2010, 10:46:19 pm
Post by: the_grim_reaper on May 18, 2010, 10:57:15 pm
Quote
can someone plzzzzzzz explain me paper 4 june 2009, question 2d, very confusing!!!!!
Friend from the previous question you'll know that ?(FX) here is 148. and ?(F) is 50
Now ?(FX) is 144 + x (x is sum of those 10 rolls)
?(F) is 60 (the total number of rolls)
148 +x
mean is 2.95 so 2.95=---------
60
so 60 X 2.95= 148 + x
so X= 177-148=29 (sum of those 10 rolls)
now mean is sum/frequency= 29/10=2.9
Post by: the_grim_reaper on May 18, 2010, 10:58:03 pm
Post by: ksitna on May 18, 2010, 11:03:54 pm
oct nov 06
8 b) iv)
Post by: SoONa on May 18, 2010, 11:06:59 pm
yes thts correct :D
yaaaaaaaaaay thank u
Post by: dsiddiqi11 on May 18, 2010, 11:13:05 pm
Friend from the previous question you'll know that ?(FX) here is 148. and ?(F) is 50
Now ?(FX) is 144 + x (x is sum of those 10 rolls)
?(F) is 60 (the total number of rolls)
148 +x
mean is 2.95 so 2.95=---------
60
so 60 X 2.95= 148 + x
so X= 177-148=29 (sum of those 10 rolls)
now mean is sum/frequency= 29/10=2.9
Thanks mate, understood it very well
Post by: ksitna on May 18, 2010, 11:15:07 pm
yaaaaaaaaaay thank u
anytime :)
Post by: NidZ- Hero on May 18, 2010, 11:17:43 pm
JUST CHILL
AND HAVE FUN MATHS IS EASY (i shuld nt be de one sayin it ) ;D :) ;)
Post by: Shazizzzle on May 18, 2010, 11:20:00 pm
i neeed help with this
oct nov 06
8 b) iv)
Q8.
b) i) Bottles: Total money/money per bottle
60.30/0.45 (45 cents = 0.45 dollars)
ii) Since both are cents, simply write the equation. x/45
iii) x-75/48
iv) Now, the number of bottles sold on tuesday were 7 more than on wednesday. Than means, wednesday lacked 7 to be equal to tuesday.
So in the eq, you give wednesday 7 more, to make it equal to tuesday. Then you put an equality and form an equation!
So No. of bottles sold on tuesday = no. of bottles sold on wednesday + 7
x/45 = x-75/48 + 7
48x - 15120 = 45x - 3375
x=3915
Post by: ksitna on May 18, 2010, 11:22:04 pm
Q8.
b) i) Bottles: Total money/money per bottle
60.30/0.45 (45 cents = 0.45 dollars)
ii) Since both are cents, simply write the equation. x/45
iii) x-75/48
iv) Now, the number of bottles sold on tuesday were 7 more than on wednesday. Than means, wednesday lacked 7 to be equal to tuesday.
So in the eq, you give wednesday 7 more, to make it equal to tuesday. Then you put an equality and form an equation!
So No. of bottles sold on tuesday = no. of bottles sold on wednesday + 7
x/45 = x-75/48 + 7
48x - 15120 = 45x - 3375
x=3915
OHHH i thought we had to multiply by 7
oh thank you so much!
Post by: Vin on May 18, 2010, 11:25:01 pm
i neeed help with this
oct nov 06
8 b) iv)
8 b) iv) easy !!
x/45 - 7 = x - 75/46
x-315/45 = x-75/48
interchange denominators
48 ( x - 315) = 45 ( x - 75)
48x - 15120 = 45x - 3375
3x = 11745
x=3915
comon wats wrong with u !!
..
Post by: NidZ- Hero on May 18, 2010, 11:50:38 pm
plzzzz can any1 help me wid o/n 2002 3c(iv) hw vil we noe dat R (-1,7)
Post by: thenewkid™ on May 19, 2010, 04:45:05 am
Post by: takamorinki on May 19, 2010, 04:50:20 am
Post by: 6394 on May 19, 2010, 05:09:49 am
mns u ll be givin invarriant 2 n u live in uae :P :P
By the way total surface area of pipe will be=2<pie>r^2+2<pie>rh -2<pie>r^2
tooo complicated lol ;D
Post by: 6394 on May 19, 2010, 05:12:08 am
mine is 4 hrs as well2 <Pie>r h is the formula for findin area of a hollow pipe!!!!
mns u ll be givin invarriant 2 n u live in uae :P :P
By the way total surface area of pipe will be=2<pie>r^2+2<pie>rh -2<pie>r^2
tooo complicated lol ;D
m i ryt
??? ???
Post by: thenewkid™ on May 19, 2010, 05:28:04 am
2 <Pie>r h is the formula for findin area of a hollow pipe!!!!its the formula 4 finding the volume of a solid cylinder
m i ryt
??? ???
Post by: thenewkid™ on May 19, 2010, 05:29:08 am
Quote
its the formula 4 finding the volume of a solid cylinderi mean 2 pi r^h
Post by: thenewkid™ on May 19, 2010, 05:29:53 am
sry
Post by: thenewkid™ on May 19, 2010, 05:38:18 am
Quote
my paper 4 is today as well! Sad just a few hours away3 hrs left
can anyone help me out with this question? i can't use trig to calculate this angle, probably just missing something really easy cuz of stress and lack of sleep: June 2005, Paper 4 question 2e
thanks a lotttt!
make a straight line down C and u'll get 90 at the bottom then cont using trig
Post by: thenewkid™ on May 19, 2010, 05:41:25 am
Quote
also, do we have to know how to make scale drawings for our current syllabus? i've never practiced it before, ever...does anyone think that will come on the paper today?there are chances but dont worry. just convert all the units to cm or mm or whatever then use the scale factor as a ratio eg; 1cm:20000000cm
Post by: thenewkid™ on May 19, 2010, 06:03:47 am
Post by: thenewkid™ on May 19, 2010, 06:39:26 am
Post by: thenewkid™ on May 19, 2010, 06:43:09 am
if yes then keep the tracing paper on the triangle and draw over it. be4 moving the paper place a dot over (0,0) and turn the paper 90 degrees anti clockwise. plce the dot on the tracing paper above (0,0) and redraw the diagram.
hope this helped.
Post by: Ghost Of Highbury on May 19, 2010, 06:48:57 am
Ok, so usually I can do transformations pretty well, like impromptu, but I'm having trouble with June 2007 Paper 4 Q. 2d)
How do you know where to draw the rotation in this case? I drew mine in quadrant 3, idk why..
If anyone can share some insight, that would be really helpful!!! ???
try this method...join the center with all the three points..
next, for each line (joining the point and the center) make a perpendicular line towards the left...(because its anticlockwise)
after uve made the respective image lines...mesaure the the length of the object line and mark a point on the image line of the exact same length..
Post by: thenewkid™ on May 19, 2010, 06:49:53 am
anyways try this. measure how far a certain point is from ur center of rotation eg A
then use a set square and plot a point the same distance away from center of rotation anticlockwise. and copy the rest of the points.
Post by: aangel42 on May 19, 2010, 06:58:07 am
try this method...join the center with all the three points..
next, for each line (joining the point and the center) make a perpendicular line towards the left...(because its anticlockwise)
after uve made the respective image lines...mesaure the the length of the object line and mark a point on the image line of the exact same length..
thanks! that makes perfect sense :)
Post by: thenewkid™ on May 19, 2010, 07:01:41 am
Post by: Ghost Of Highbury on May 19, 2010, 07:05:41 am
thanks! that makes perfect sense :)
Good luck for paper 4..
Post by: Ghost Of Highbury on May 19, 2010, 07:05:53 am
getting ready, leaving in 15 min, pray 4 me ppl
Good luck..!
Post by: Baladya on May 19, 2010, 07:07:52 am
6)b)ii) plzzzz help i dunno how i forgot it right now :S :-[ :-[ :-[ :-[ :-[
Post by: Ghost Of Highbury on May 19, 2010, 07:10:41 am
http://www.freeexampapers.us/IGCSE/Maths/CIE/2008%20Nov/0580_w08_qp_04.pdf (http://www.freeexampapers.us/IGCSE/Maths/CIE/2008%20Nov/0580_w08_qp_04.pdf)
6)b)ii) plzzzz help i dunno how i forgot it right now :S :-[ :-[ :-[ :-[ :-[
okk..heres how u do it..
---------------RULE---------------------------------------------------
if class width = n * standard width, then, height = frequency/n
--------------------------------------------------------------------------
first lets find the standard width...the height given = 11.5, its frequency is 115
therefore 11.5 = 115/n...=> n = 10
class width = 10 * standard width
2 = 10 * standard width
therefore standard width = 0.2
-----------------------------------------------------
now use this formula with standard width 0.2 to calculate the heights..
height = fequency * (standard width/classwidth)
1st - h = 35 * 0.2/10 = 0.7
2nd - 11.5 (given)
3rd - h = 26 * 0.2/2 = 2.6
4th - h = 24 * 0.2/6 = 0.8
Post by: princess12 on May 19, 2010, 07:21:16 am
why 4 hours 6394
reoly me fast urgently please ??? ??? ??? ??? ??? ??? ??? ??? ??? ???
Post by: 6394 on May 19, 2010, 07:21:31 am
pray for me ppl
INSHAALLAH its gonna b easy 4 all ov us
BEST OF LUCK
:) ;) :D ;D ::) :P
Post by: 6394 on May 19, 2010, 07:22:47 am
mine is 4 hrs as wellat de tym i postd 4 hrs wer lft 4 de ppr to start
why 4 hours 6394
reoly me fast urgently please ??? ??? ??? ??? ??? ??? ??? ??? ??? ???
ohk gud lck
:) :)
Post by: 6394 on May 19, 2010, 07:23:32 am
at de tym i postd 4 hrs wer lft 4 de ppr to startu live in uae???????
ohk gud lck
:) :)
Post by: princess12 on May 19, 2010, 07:23:59 am
after 30 minutes guys pray for me
goodluck
Post by: mdwael on May 19, 2010, 07:24:45 am
Post by: Baladya on May 19, 2010, 07:26:24 am
okk..heres how u do it..
---------------RULE---------------------------------------------------
if class width = n * standard width, then, height = frequency/n
--------------------------------------------------------------------------
first lets find the standard width...the height given = 11.5, its frequency is 115
therefore 11.5 = 115/n...=> n = 10
class width = 10 * standard width
2 = 10 * standard width
therefore standard width = 0.2
-----------------------------------------------------
now use this formula with standard width 0.2 to calculate the heights..
height = fequency * (standard width/classwidth)
1st - h = 35 * 0.2/10 = 0.7
2nd - 11.5 (given)
3rd - h = 26 * 0.2/2 = 2.6
4th - h = 24 * 0.2/6 = 0.8
Dude, u saved my A** THNAKKKKSSSSSS 0.0 :) :) :) :)
Post by: 6394 on May 19, 2010, 07:27:22 am
m leavin nowya sure
after 30 minutes guys pray for megoodluck
Post by: LM on May 19, 2010, 08:01:46 am
GOOD LUCK GUYSS!!
Post by: Saavya on May 19, 2010, 08:15:58 am
Post by: PeaceMaker on May 19, 2010, 08:18:26 am
1 hour n 45min to go (UAE) :-X hehh only this one and i will be able to do the others without any tension :-[
Agreed. Only maths is the problem because its never ending!
Post by: CatAly$t on May 19, 2010, 09:38:08 am
MAths paper 4 is very hard!!!!!!!!!!!!!Nobody in my school solved the last page!!!!
Post by: Candela on May 19, 2010, 11:07:47 am
Post by: Ghost Of Highbury on May 19, 2010, 11:12:27 am
Post by: CatAly$t on May 19, 2010, 11:13:51 am
Post by: nizzy on May 19, 2010, 11:21:38 am
Post by: Baladya on May 19, 2010, 11:37:09 am
By the way do u think it was harder or easier than the past exam? I think it was harder but i did so good :D
Post by: luv3life on May 19, 2010, 11:40:22 am
Anyone else did it yet? How was it for you guys? :D
Post by: luv3life on May 19, 2010, 12:21:14 pm
Post by: luv3life on May 19, 2010, 12:49:19 pm
Post by: soualhi1 on May 19, 2010, 01:29:03 pm
NO MORE MATHS FOR ANOTHER TWO YEARS!!
Post by: luv3life on May 19, 2010, 01:39:27 pm
Post by: contraentry on May 19, 2010, 01:57:57 pm
I agree, aangel42. Some tricky questions, like diffrent ones, but not so hard. :) lol. What du have next?
Exactly how I feel! I got the last question and the invigilator was like "STOP WRITING NOW PLEASE, EXAMINATION IS OVER" :( I made a silly mistake somewhere, and an honest mistake another place, but will wait till 24hrs have passed till discussion. Overall, I feel confident about this paper! Inshallah we will all get good marks!
Post by: luv3life on May 19, 2010, 02:03:36 pm
Aim High. :D
Post by: dsiddiqi11 on May 19, 2010, 02:16:51 pm
Post by: The Golden Girl =D on May 19, 2010, 02:25:35 pm
YAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAY
Post by: Parth.H on May 19, 2010, 02:32:26 pm
Post by: The Golden Girl =D on May 19, 2010, 02:33:57 pm
im srry but it's agianst the site's rules to discuss an exam before 24 hrss have passed
Post by: 6394 on May 19, 2010, 02:38:53 pm
my ppr wsnt gud
:( :( :( :(
it was hard
ppr 2 was easy n i did a lot of silly mistakes
n ppr 4 was hard :( :( :(
maths ovrall went bad 4 me :( :( :(
Post by: Vin on May 19, 2010, 02:41:11 pm
Cheer up .. leave it to God .. do well in other papers .. ;) ;)
Post by: 6394 on May 19, 2010, 03:00:37 pm
Cheer up .. leave it to God .. do well in other papers .. ;) ;)Thanks for de encouragemnt :) :) :)
do pray for me ppl
Post by: luv3life on May 19, 2010, 03:01:40 pm
Post by: 6394 on May 19, 2010, 03:03:45 pm
I pray for everyone, before I do my exams, every time, lol. :)i do it as wel
:) :) :P ;D
Post by: The Golden Girl =D on May 19, 2010, 03:05:05 pm
I pray for everyone, before I do my exams, every time, lol. :)
wallah , then god bless both of u ;)
Post by: luv3life on May 19, 2010, 03:08:54 pm
Post by: 6394 on May 19, 2010, 03:14:13 pm
wallah , then god bless both of u ;)INSHAALLAH
ALLAH will bless all of us
:)
Post by: The Golden Girl =D on May 19, 2010, 03:16:21 pm
INSHAALLAH
ALLAH will bless all of us
:)
inshAllah ;)
Post by: 6394 on May 19, 2010, 03:16:35 pm
hoeevr is givin because m not :P
gud luk
n m depressed abt maths wat shud i do??????
Post by: Adzel on May 19, 2010, 03:17:03 pm
Post by: The Golden Girl =D on May 19, 2010, 03:19:26 pm
How do you pray for someone....By the way I think you're supposed to say "I make DUA for someone". Cuz I only pray to ALLAH.... :-\
ya Adzel ,il ajanib wa 3'eer il3arab yi8uloon i'll pray for u bass il muslimeen yu8uloon dua'a .......wa na7na 8ilna pray 3ashan il kil yifhamna :D .......la ta5f il kil prays li Allah
Post by: Adzel on May 19, 2010, 03:22:03 pm
ya Adzel ,il ajanib wa 3'eer il3arab yi8uloon i'll pray for u bass il muslimeen yu8uloon dua'a .......wa na7na 8ilna pray 3ashan il kil yifhamna :D .......la ta5f il kil prays li Allah
3'reeb....Makint a3raf hatha :-\
Post by: The Golden Girl =D on May 19, 2010, 03:23:39 pm
3'reeb....Makint a3raf hatha :-\
no probs 2a7een ta3rif , sa7? ....
Post by: luv3life on May 19, 2010, 03:27:04 pm
Post by: Vin on May 19, 2010, 03:30:03 pm
Its Arabic .. ;) i pray for all sentient beings on this earth !! =P
Post by: The Golden Girl =D on May 19, 2010, 03:35:58 pm
By the way best of luk 4 bio ppr 6
hoeevr is givin because m not :P
gud luk
n m depressed abt maths wat shud i do??????
study for the next subject u have and go wash ur face ...t3awathi min ishaytan ........ la tfakireen anymore fi ilimti7an .....id3i Allah ino yewafgch bi bagi il imti7anat ,zeen ? ...... ya allah bitwafee8 insAllah
Post by: The Golden Girl =D on May 19, 2010, 03:37:03 pm
Its Arabic .. ;) i pray for all sentient beings on this earth !! =P
how did u kno it's arabic!?!? ..lol..and what did u say in the last sentence? :-\
Post by: takamorinki on May 19, 2010, 03:37:34 pm
it was good :D i came in the hall without a calculator >.> just realize after i taken my sit
fail.. wanna hear the whole story go Here (ftp://http://danniellkidman.deviantart.com/journal/32289409/)
Maths paper 4 was long
Post by: Adzel on May 19, 2010, 03:40:03 pm
Post by: The Golden Girl =D on May 19, 2010, 03:42:30 pm
By the way golden girl how was 3arabi paper 1 reading....I found it easy
fashaltni lol ...ana 3arabya bass ma 2a5ith 3arabi ..ila ili ilwizara forced us to study ...(fashla :-[ :-[ :-[ :-X)
Post by: ~HyDrOgEn~ on May 19, 2010, 03:45:01 pm
Golden girl any suggestions for paper 6 tomorrow !
Post by: The Golden Girl =D on May 19, 2010, 03:45:44 pm
Golden girl any suggestions for paper 6 tomorrow !
actually i did write smthn in the chem and bio doubts wait i'll get it for u ,k?
read this
https://studentforums.biz/index.php/topic,7969.0.html
1. the classification chapter
2.experiments on germination (effect of water,temp,oxgen on germination)
3.experiments on the factors of photosynthesis (light, carbon dioxide,temperature )
4.differences between monoct and dicot plants
5.labellings for a flower,a snail,a seed ,an insect
6.u should kno what kind of imporvements to make in eeach experiment there is in the paper but reading the table and question twice cuz the answer is there .( i wanna tell u more but i am too busy to type more)
7.how to detect transpiration (place a plastic bag on the plant ,water will condense)
8.effect of cutting roots of a seedling (wilts when cut , when not cut is healthy and upright)
9.effect of cutting roots of a plants on it's water uptake
10.u gotta what a bill jar is and thatit's used for testin for breathing
11. test for the different scents of plants and the effect of it on attracting insects (i wanna describe the exp but it's too long and i'm busy . sooo google it or smthn , k?)
12.test for the effect of colour of petal of a flower on the attracting of insects (google this too! )
13.exp on pulse rate of a runner and person whose not doin excersice
14.testin of carbon dioxide, and oxgen
15.test of finding the reaction time of a person
16.tests abt the effect of auxin on phototropism, and Geotropism
ohhh and solve a dozen of past papers , cya
Post by: ~HyDrOgEn~ on May 19, 2010, 03:47:04 pm
how come you guys use numbers in the middle of words when you write? like 3, 7, 8?OK ;)
Post by: The Golden Girl =D on May 19, 2010, 03:49:58 pm
how come you guys use numbers in the middle of words when you write? like 3, 7, 8?
u kno in englis there is a slang language ..well in arabic we have numbers that stand for letters , so if u kno the rules for the arabic MSn lagnauge u can talk to all arabs around the wrold cuz every arab knows is :D
Post by: Adzel on May 19, 2010, 03:51:32 pm
how come you guys use numbers in the middle of words when you write? like 3, 7, 8?
Some numbers we use them, cuz there is some arabic letters which are not the same as english ;)....
Post by: mdwael on May 19, 2010, 03:53:08 pm
Anyone so good at bio?
Post by: ~HyDrOgEn~ on May 19, 2010, 03:57:18 pm
how come you guys use numbers in the middle of words when you write? like 3, 7, 8?Thanks Sister !
Post by: luv3life on May 19, 2010, 04:00:21 pm
Post by: Ghost Of Highbury on May 19, 2010, 04:06:37 pm
Post by: luv3life on May 19, 2010, 04:16:49 pm
Post by: Ghost Of Highbury on May 19, 2010, 04:24:11 pm
A@di: Oh yeah! I'm sooo sorry! For give me? :-[ I'm so stressed, not even looking at the thread names!~
Its okay, no problem.. :)
Post by: Dibss on May 19, 2010, 04:26:59 pm
@Dibssi'm sorry my internet stopped working last night and i couldn't reply. i meant to say that venn diagram i attached failed to upload hence the insufficient info.
u want the solution ??
Thank you so much though! you have a very positive presence in this thread :]
The question is from O/N/05. Question 4.thank you for the info! i checked the mark scheme immediately when i saw your post yesterday and it turned out that yes, my teacher was incorrect :P
Post by: aangel42 on May 19, 2010, 04:37:31 pm
actually i did write smthn in the chem and bio doubts wait i'll get it for u ,k?
read this
https://studentforums.biz/index.php/topic,7969.0.html
1. the classification chapter
2.experiments on germination (effect of water,temp,oxgen on germination)
3.experiments on the factors of photosynthesis (light, carbon dioxide,temperature )
4.differences between monoct and dicot plants
5.labellings for a flower,a snail,a seed ,an insect
6.u should kno what kind of imporvements to make in eeach experiment there is in the paper but reading the table and question twice cuz the answer is there .( i wanna tell u more but i am too busy to type more)
7.how to detect transpiration (place a plastic bag on the plant ,water will condense)
8.effect of cutting roots of a seedling (wilts when cut , when not cut is healthy and upright)
9.effect of cutting roots of a plants on it's water uptake
10.u gotta what a bill jar is and thatit's used for testin for breathing
11. test for the different scents of plants and the effect of it on attracting insects (i wanna describe the exp but it's too long and i'm busy . sooo google it or smthn , k?)
12.test for the effect of colour of petal of a flower on the attracting of insects (google this too! )
13.exp on pulse rate of a runner and person whose not doin excersice
14.testin of carbon dioxide, and oxgen
15.test of finding the reaction time of a person
16.tests abt the effect of auxin on phototropism, and Geotropism
ohhh and solve a dozen of past papers , cya
do we really have to know the following (because they're not mentioned anywhere in the syllabus, textbook, or study guide...) :
10.u gotta what a bill jar is and thatit's used for testin for breathing
11. test for the different scents of plants and the effect of it on attracting insects (i wanna describe the exp but it's too long and i'm busy . sooo google it or smthn , k?)
12.test for the effect of colour of petal of a flower on the attracting of insects (google this too! )
Post by: Ghost Of Highbury on May 19, 2010, 04:38:18 pm
:D
Post by: Vin on May 19, 2010, 06:24:40 pm
lol guys chill .. read the thread title .. =P
Post by: Amberr on May 19, 2010, 06:57:56 pm
By the way GUYS PAPER 4 WAS EASIER THAN PAPER 2!!!!!!!!!!!! i know i've lost one mark tho :(
anywayyyssss...tommorow... start discussing with u guyssss!!!!!
stay onlinee.. i have questionsss :))))
Post by: The Golden Girl =D on May 19, 2010, 07:57:16 pm
do we really have to know the following (because they're not mentioned anywhere in the syllabus, textbook, or study guide...) :
10.u gotta what a bill jar is and thatit's used for testin for breathing
11. test for the different scents of plants and the effect of it on attracting insects (i wanna describe the exp but it's too long and i'm busy . sooo google it or smthn , k?)
12.test for the effect of colour of petal of a flower on the attracting of insects (google this too! )
actually no. 12 is in the past paper i guess year jun 2005 , check it .
as for the rest , they were tips from my bio tutor
gd luck angel in ur exam tomw !
Post by: Dibss on May 19, 2010, 08:00:33 pm
LOL guyz, this is the math thread, plz discuss elsewhere..
:D
lol guys chill .. read the thread title .. =P
...and then there was bio ;)
Post by: diva_sparkles on May 19, 2010, 08:30:51 pm
actually no. 12 is in the past paper i guess year jun 2005 , check it .
as for the rest , they were tips from my bio tutor
gd luck angel in ur exam tomw !
hey isnt it a bell jar
Post by: diva_sparkles on May 19, 2010, 08:47:43 pm
yeah it is
http://docs.google.com/viewer?a=v&q=cache:LPIODzCpfIoJ:www.ise5-14.org.uk/members/Glasgow/BREATHDI.PDF+testing+for+breathing+bell+jar&hl=en&pid=bl&srcid=ADGEESjiQPQBnkfI5oHST5DqEEXw0wm2haPpuWB7cG6saaORstxWofPZpLLoHp0-OUHjahB1qEraHacKz3445gkAuLj-OvnsWqo5yzNQYf9Q9RcL4lPMLgFEG1jezg0b3dsqAqjobJ2c&sig=AHIEtbSwe5MmyC1ipkTVThslmQGzEACTvA
has that ever been on a past paper before? (please say no please say no...)
no but a bit similar n it wz very easy
Post by: 6394 on May 20, 2010, 07:39:52 am
study for the next subject u have and go wash ur face ...t3awathi min ishaytan ........ la tfakireen anymore fi ilimti7an .....id3i Allah ino yewafgch bi bagi il imti7anat ,zeen ? ...... ya allah bitwafee8 insAllahm sry dint understand the last sentece " fi ilimti7an .....id3i Allah ino yewafgch bi bagi il imti7anat ,zeen ? ...... ya allah bitwafee8 insAllah " fully thou i got some parts "t3awathi min ishaytan ........ la tfakireen anymore" n Thanks
k explain me this b4 i usd 2 think u ppl wen writin arabic by mistakenly add nos.
bt i ve noticed u add it lik in evry sent. esp.3 n 7
wat r dese nos.
n hw was bio ppr 6 for u pple
Post by: Ghost Of Highbury on May 20, 2010, 07:44:29 am
Post by: The Golden Girl =D on May 20, 2010, 08:19:19 am
m sry dint understand the last sentece " fi ilimti7an .....id3i Allah ino yewafgch bi bagi il imti7anat ,zeen ? ...... ya allah bitwafee8 insAllah " fully thou i got some parts "t3awathi min ishaytan ........ la tfakireen anymore" n Thanks
k explain me this b4 i usd 2 think u ppl wen writin arabic by mistakenly add nos.
bt i ve noticed u add it lik in evry sent. esp.3 n 7
wat r dese nos.
n hw was bio ppr 6 for u pple
wait so ur not an Arab ?! ??? cuz everything i told u was in Arabic
Post by: Ghost Of Highbury on May 20, 2010, 08:28:02 am
wait so ur not an Arab ?! ??? cuz everything i told u was in Arabic
Golden girl - This is the 4th time, This is a Math thread, plz refrain from discussing abt arabic/biology :)
Post by: The Golden Girl =D on May 20, 2010, 08:35:45 am
Golden girl - This is the 4th time, This is a Math thread, plz refrain from discussing abt arabic/biology :)
i'm really srry it's just that i got soooo interested in talkin in arabic cuz all the time i am talkin englsih over here
P.S. sry ,i'll try my best not to talk abt these two in any of the threads :-X :-X
anyone who wants to talk with me or anyone in arabic go to the folllowing thread ::)
https://studentforums.biz/index.php/topic,8003.msg212257.html#msg212257
again srry A@di :'(
Post by: Ghost Of Highbury on May 20, 2010, 08:38:32 am
i'm really srry it's just that i got soooo interested in talkin in arabic cuz all the time i am talkin englsih over here
P.S. sry ,i'll try my best not to talk abt these two in any of the threads :-X :-X
anyone who wants to talk with me or anyone in arabic go to the folllowing thread ::)
https://studentforums.biz/index.php/topic,8003.msg212257.html#msg212257
again srry A@di :'(
You can talk abt arabic and biology but in their respective threads, or General Talk. Not in the IGCSE maths thread.
Post by: luv3life on May 20, 2010, 11:06:29 am
Post by: ksitna on May 20, 2010, 11:07:03 am
Post by: holtadit on May 20, 2010, 11:08:53 am
Go discuss there.
Post by: Borat3169 on May 20, 2010, 03:27:32 pm
:D ;D!!!!!!!!GOOD LUCK PEOPLE!!!!!!!!! ;D :D
Post by: Choc.Kits on May 25, 2010, 05:59:45 pm
Post by: eastrimx on May 29, 2010, 04:48:09 pm
Post by: Ghost Of Highbury on May 29, 2010, 07:49:29 pm
a = first no.
d = difference
c = final difference
n = nth term
Post by: The Golden Girl =D on May 29, 2010, 07:56:46 pm
a+(n-1)d + 0.5(n-1)(n-2)c
a = first no.
d = difference
c = final difference
n = nth term
my teacher say s that no matter what equations teachers give u , sequence has many equations that even uni students keeo leranin
Post by: contraentry on May 29, 2010, 08:24:23 pm
my teacher say s that no matter what equations teachers give u , sequence has many equations that even uni students keeo leranin
Wow, thats the same thing that my teacher told me as well, actually, she referred to the last question as an Out Of Syllabus question.
Post by: The Golden Girl =D on May 29, 2010, 08:25:35 pm
Wow, thats the same thing that my teacher told me as well, actually, she referred to the last question as an Out Of Syllabus question.
yah same idea ;)
Post by: the_grim_reaper on May 30, 2010, 07:13:55 pm
Post by: Ghost Of Highbury on May 30, 2010, 07:15:31 pm
By the way how many of you did variant 2?? I did variant 2 and the last question was a bit tough but still easier than the stuff they're giving these days. I mean the sequences in MJ09 or Oct09 are insolvable. Unless of course you're Einstein's son...
of course it can be solved..i gave the on 2009 paper and i cud solve it, and so could all of my friends..
u hav to subtract the sequences of the previous 2 rows..thats it..
Post by: the_grim_reaper on May 30, 2010, 07:17:00 pm
of course it can be solved..i gave the on 2009 paper and i cud solve it, and so could all of my friends..
u hav to subtract the sequences of the previous 2 rows..thats it..
Like I said, you'll have to be related to Einstein to solve them ;D...
Post by: holtadit on June 02, 2010, 08:08:57 am
Time for it to drift into the abyss !! :P
GOODBYE !!!
Post by: Meticulous on June 02, 2010, 08:36:38 am
Post by: holtadit on June 02, 2010, 08:42:12 am
LOL it's maths, not physics. You just copied and pasted :P
::)
Its tiring when you have to keep typing a custom message for each topic.... :P