IGCSE MATHS Doubts

[Saladin]

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.

[Vin]

okay so Texas TI-30XB is allowed right??

[Saladin]

I have never used TI.

Please ask CIE here

[Ghost Of Highbury]

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.

[haris94]

ofcourse calculators are allowed

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)

[Baladya]

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

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 xD

Quicki for dummies : 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 : 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

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

[Vin]

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..!! 

[Vin]

@baladya

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

[Ghost Of Highbury]

omg.... I dunno what will i do in the IGCSE if i do these mistakes :S
Anyway thx man

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 xD

Quicki for dummies : 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 : 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

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

[Ghost Of Highbury]

The opposite angles of a cyclic quadrilateral add up to 180.

[Ghost Of Highbury]

ii) x = 40 degree (alternate angles)
   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.

[haris94]

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

[Vin]

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

[Vin]

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..
 

[The Golden Girl =D]

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   "