IGCSE/GCSE/O & A Level/IB/University Student Forum

Qualification => Subject Doubts => IGCSE/ GCSE => Math => Topic started by: angell on May 17, 2009, 08:49:42 pm

Title: ON 08 P4 HELP MATH!!
Post by: angell on May 17, 2009, 08:49:42 pm
Q.4 C plz:(
Title: Re: ON 08 P4 HELP MATH!!
Post by: al noor on May 17, 2009, 09:09:42 pm
Please attatch the question maybe i can help you ???
Title: Re: ON 08 P4 HELP MATH!!
Post by: theigstudent on May 17, 2009, 09:13:16 pm
Q.4 C plz:(
hey plz help even i m stuck on this 1
plzzzz help

Title: Re: ON 08 P4 HELP MATH!!
Post by: al noor on May 17, 2009, 09:37:58 pm
Q.4 C plz:(
hey plz help even i m stuck on this 1
plzzzz help



Please attach the question soo i can help
Title: Re: ON 08 P4 HELP MATH!!
Post by: angell on May 17, 2009, 09:40:30 pm
Q4c
5e
 and complete Q 9 PLEASE:(
Title: Re: ON 08 P4 HELP MATH!!
Post by: theigstudent on May 17, 2009, 09:49:03 pm
Q4c
5e
 and complete Q 9 PLEASE:(
so did u get Q8 a
could u plz explain it to me
Title: Re: ON 08 P4 HELP MATH!!
Post by: al noor on May 17, 2009, 09:52:33 pm
Q4c
5e
 and complete Q 9 PLEASE:(

Ummm sorry for Q4c i am nt suree sorry

But for Q5e...is : first draw a right angle triangle from and it ends in C
Sin 60.2=OPP/HYP
sin 60.2=OPP/85 = 73.76km


Q9 is :
a)        P =42-(12+17+8)  =5
           Q= (40-(20+8)=12
           R= 1

b) i) 17
    ii)12

c) i) 26
    ii)57

d)   i) 8/100= 2/25
      ii) 45/100=9/20

e) 37/74 * 36/73 and then u can find the answer

Hope i helped u ..and gud luck ;)
Title: Re: ON 08 P4 HELP MATH!!
Post by: sanity_master on May 17, 2009, 09:57:36 pm
Q4 C

u have to add the 2 pentagons = 536 X 2 =1070

drop a line from ) to the center of AB

then get AB by >>  sin 36 = (AB÷2)
                                            15
= 17.63

the total = (17.63X 5)+ 1070 = 5477.5 cm2

if u dont understand anything from the solution tell me
Title: Re: ON 08 P4 HELP MATH!!
Post by: al noor on May 17, 2009, 09:58:18 pm
Q4c
5e
 and complete Q 9 PLEASE:(
so did u get Q8 a
could u plz explain it to me

x=78(bcoz alternate angle)
y=180-36=144(bcoz opposite angle of cyclic quadratic)
z=180-78=102(bcoz opposite angle of cyclic quadratic)
 oki??
Title: Re: ON 08 P4 HELP MATH!!
Post by: theigstudent on May 17, 2009, 10:06:19 pm
thanks a lot guys
the explanations were superb  :)
Thanks once again
Title: Re: ON 08 P4 HELP MATH!!
Post by: sanity_master on May 17, 2009, 10:08:14 pm
ur welcome.....glad i could help :)
Title: Re: ON 08 P4 HELP MATH!!
Post by: theigstudent on May 17, 2009, 10:09:46 pm
 :) a +rep 4 all u guys :)
Title: Re: ON 08 P4 HELP MATH!!
Post by: al noor on May 17, 2009, 10:11:32 pm
ur welcome.....glad i could help :)

can u add my rep plzz :)
Title: Re: ON 08 P4 HELP MATH!!
Post by: angell on May 17, 2009, 10:12:55 pm
yup thankx!!! +Rep from me too

but 1 more doubt

may/june 2008

q10
d)i d)ii and d)iii
Title: Re: ON 08 P4 HELP MATH!!
Post by: sanity_master on May 17, 2009, 10:14:56 pm
check the topic i made about it ZARA answered it.....
https://studentforums.biz/index.php/topic,1460.0.html


add to that N08.....Q 10i solved it but i dont fully get it :S....

anyone
Title: Re: ON 08 P4 HELP MATH!!
Post by: astarmathsandphysics on May 17, 2009, 10:25:48 pm
yup thankx!!! +Rep from me too

but 1 more doubt

may/june 2008

q10
d)i d)ii and d)iii
i)(x+2n+2-x)-(x+2n-x-2)=4
ii)g=x+2n i=x+2n+2
iii)(x+2n+2)x-(x+2n)(x+2)=-4n
Title: Re: ON 08 P4 HELP MATH!!
Post by: astarmathsandphysics on May 17, 2009, 10:27:36 pm
check the topic i made about it ZARA answered it.....
https://studentforums.biz/index.php/topic,1460.0.html


add to that N08.....Q 10i solved it but i dont fully get it :S....

anyone
Is that ai) bi) or ci)
Title: Re: ON 08 P4 HELP MATH!!
Post by: theigstudent on May 17, 2009, 10:28:24 pm
yup thankx!!! +Rep from me too

but 1 more doubt

may/june 2008

q10
d)i d)ii and d)iii
i)(x+2n+2-x)-(x+2n-x-2)=4
ii)g=x+2n i=x+2n+2
iii)(x+2n+2)x-(x+2n)(x+2)=-4n


Thanks
coul u plz explain how did u get  g  and   i
Title: Re: ON 08 P4 HELP MATH!!
Post by: astarmathsandphysics on May 17, 2009, 10:30:51 pm
Go down 2 rows means add 2n. Go right 2 colums means add 2.
Title: Re: ON 08 P4 HELP MATH!!
Post by: theigstudent on May 17, 2009, 10:32:03 pm
Go down 2 rows means add 2n. Go right 2 colums means add 2.


wow i din't know that Thanks a million
Title: Re: ON 08 P4 HELP MATH!!
Post by: sanity_master on May 17, 2009, 10:36:26 pm
check the topic i made about it ZARA answered it.....
https://studentforums.biz/index.php/topic,1460.0.html


add to that N08.....Q 10i solved it but i dont fully get it :S....

anyone
Is that ai) bi) or ci)

all of it plz!!

the weird thing is that i did solve it all.....but i dont fully get it, lucky shot when solving it i guess

plz explain it
Title: Re: ON 08 P4 HELP MATH!!
Post by: twilight on May 17, 2009, 10:36:55 pm
can u attach the paper? .. mayb i can help
Title: Re: ON 08 P4 HELP MATH!!
Post by: theigstudent on May 17, 2009, 10:44:44 pm
check the topic i made about it ZARA answered it.....
https://studentforums.biz/index.php/topic,1460.0.html


add to that N08.....Q 10i solved it but i dont fully get it :S....

anyone
Is that ai) bi) or ci)

all of it plz!!

the weird thing is that i did solve it all.....but i dont fully get it, lucky shot when solving it i guess

plz explain it
as in 10 a to 10 d
Title: Re: ON 08 P4 HELP MATH!!
Post by: sanity_master on May 17, 2009, 10:45:37 pm
Q 10
Title: Re: ON 08 P4 HELP MATH!!
Post by: theigstudent on May 17, 2009, 10:46:19 pm
can u attach the paper? .. mayb i can help

the link is attached to the 5 th post(by angell)
Title: Re: ON 08 P4 HELP MATH!!
Post by: astarmathsandphysics on May 17, 2009, 10:48:33 pm
                1 + 2 + 3 + 4 + 5 + .................................. + n = n(n +1)
10
                                                                             2
   (a) (i) Show that this formula is true for the sum of the first 8 natural numbers.               [2]
       (ii) Find the sum of the first 400 natural numbers.                                          [1]
   (b) (i) Show that 2 + 4 + 6 + 8 + ..................... + 2n = n(n + 1).                                     [1]
       (ii) Find the sum of the first 200 even numbers.                                             [1]
      (iii) Find the sum of the first 200 odd numbers.                                              [1]
   (c) (i) Use the formula at the beginning of the question to find the sum of the first 2n natural
            numbers.                                                                                [1]
       (ii) Find a formula, in its simplest form, for
                1 + 3 + 5 + 7 + 9 + ........................ + (2n – 1).
                                                                                                    [2]
            Show your working.
ai)1+2+3+4+5+6+7+8=6=8/2(8+1)
ii)400(400+1)/2=80200
bi)AMS=2* the sum of the first 200 odd numbers=2*200(201)/2=40200
ii)ANS = sum of first 400 numbers- sum of first200 even numbers=80200-40200=40000
ci)2n(2n+1)/2=2n^2+n
ii)ANS=sum of firast wn numbers - sum of first 2n even numbers=2n^2+n- 2* sum of first n numbers=2n^2+n-2n(n+1)/2=n^2
Title: Re: ON 08 P4 HELP MATH!!
Post by: theigstudent on May 17, 2009, 10:50:11 pm
wow astar such a long post
Title: Re: ON 08 P4 HELP MATH!!
Post by: angell on May 17, 2009, 10:51:55 pm
im failing tmorrw:'(
Title: Re: ON 08 P4 HELP MATH!!
Post by: sanity_master on May 17, 2009, 10:52:08 pm
yet i couldnt get it but Thanks.....lets just hope a Q like that is not in the exam tom.  :-\
Title: Re: ON 08 P4 HELP MATH!!
Post by: sanity_master on May 17, 2009, 10:54:20 pm
i g2g ppl.......Talk to you later

and gd luck tomorrow.....we rabena yostor!!  :(
Title: Re: ON 08 P4 HELP MATH!!
Post by: astarmathsandphysics on May 17, 2009, 10:55:24 pm
Quite tricky. Leave it til last and do the best you can.
Title: Re: ON 08 P4 HELP MATH!!
Post by: theigstudent on May 17, 2009, 10:57:14 pm
could some 1 explain Q7 a ii
how do u get y and z
same paper ???
Title: Re: ON 08 P4 HELP MATH!!
Post by: astarmathsandphysics on May 17, 2009, 11:01:00 pm
Rflection in line x=1? Is it Nov 08
Title: Re: ON 08 P4 HELP MATH!!
Post by: theigstudent on May 17, 2009, 11:02:31 pm
Rflection in line x=1? Is it Nov 08
no its june o8
Title: Re: ON 08 P4 HELP MATH!!
Post by: astarmathsandphysics on May 17, 2009, 11:05:24 pm
OAB is isoceles since )A and OB are radii. therefore y=(180-130)/2=25

ST and Ob are parelell so by Z rule x=40
ABC and ADB sum to 180 so z=180-(25+40)=115
Title: Re: ON 08 P4 HELP MATH!!
Post by: angell on May 17, 2009, 11:10:44 pm
thank u so much for the prompt replies!!:D
Title: Re: ON 08 P4 HELP MATH!!
Post by: theigstudent on May 17, 2009, 11:12:28 pm
OAB is isoceles since )A and OB are radii. therefore y=(180-130)/2=25

ST and Ob are parelell so by Z rule x=40
ABC and ADB sum to 180 so z=180-(25+40)=115

how to get y =25


n Thanks a lottttt for such instant replies

Title: Re: ON 08 P4 HELP MATH!!
Post by: twilight on May 17, 2009, 11:18:28 pm
like astar said .. AO and OB are equal bcoz they r radii .. so triangle AOB is isosceles ..
the sum of the angles is 180 .. so
angle OAB = angle OBA             and     OAB + OBA + 130 = 180    =>   OBA + OBA + 130 = 180

so 2y + 130 = 180            => y=25
Title: Re: ON 08 P4 HELP MATH!!
Post by: theigstudent on May 17, 2009, 11:23:38 pm
oh ya  it so simple
Thanks a lot ppl
i needa go because in next six hours i have to reach ma school 4 exam
best of luck to every1
Title: Re: ON 08 P4 HELP MATH!!
Post by: archangel on May 18, 2009, 03:43:38 am
ahh i need help, my exam is in 3 hours  :-\

do u guys know q7 part d)

why is the answer 57?
shouldnt it be 180-(78 x 2) = 24?

because if its isoceles than i can use that method right?
Title: Re: ON 08 P4 HELP MATH!!
Post by: astarmathsandphysics on May 18, 2009, 07:42:52 am
q7 doesnt have a d)
Title: Re: ON 08 P4 HELP MATH!!
Post by: sanity_master on May 18, 2009, 07:44:40 am
LOL :D.........every one is nervous

my xam is in 3 hours and 17 minutes !  :'(

God be with me....


good luck everyone :)