Mathematics: Post your doubts here!

[TERMINATOR]

i cant read the question,attachment is not viewing full size.

mark scheme

 

[Browny]

http://papers.xtremepapers.com/CIE/...S Level/Mathematics (9709)/9709_s12_qp_11.pdf

7)b)i)

Can anyone please explain I don't understand the method in the marking scheme and why don't we use -1<.......<1?

 

[CЯeScɘnt]

View attachment 41039

mark scheme

View attachment 41040

let tan*=tan inverse
tan*2+tan*3
=arg(1+2i) - arg(1-3i)
=arg((1+2i)/(1-3i)) =>this is because arg(a) -arg(b) = arg(a/b)
=arg(u)
=pi by 4

 

[TERMINATOR]

let tan*=tan inverse
tan*2+tan*3
=arg(1+2i) - arg(1-3i)
=arg((1+2i)/(1-3i)) =>this is because arg(a) -arg(b) = arg(a/b)
=arg(u)
=pi by 4

Thank you. I highly appreciate your help.

 

[CЯeScɘnt]

Thank you. I highly appreciate your help.

my pleasure to help

 

[Ameena Eesa]

Can anyone help plz................... the ans is correct but ho to solve in steps?

 

[Ameena Eesa]

Help..............

 

[CЯeScɘnt]

http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Mathematics (9709)/9709_s12_qp_11.pdf

7)b)i)

Can anyone please explain I don't understand the method in the marking scheme and why don't we use -1<.......<1?

for 1/3 tan^2 x to be convergent,
it should be less then 1 n as x is greater then zero then it should be greater then zero,so this implies
0<1/3 tan^2 x<3
now make x subject
multiply through out by 3 then take square root through out n then tan inverse
this will give u the answer.
if still not clear,dont hesitate to ask

 

[CЯeScɘnt]

Can anyone help plz................... the ans is correct but ho to solve in steps?View attachment 41041

sweetheart its A level mathematics forum

 

[Browny]

for 1/3 tan^2 x to be convergent,
it should be less then 1 n as x is greater then zero then it should be greater then zero,so this implies
0<1/3 tan^2 x<3
now make x subject
multiply through out by 3 then take square root through out n then tan inverse
this will give u the answer.
if still not clear,dont hesitate to ask

Can you go through that in detail please I still didn't get it?

 

[Faaiz Haque]

http://papers.xtremepapers.com/CIE/...AS Level/Mathematics (9709)/9709_s09_qp_1.pdf
Question 10) i ii iii, with some brief explanations. i'd like to see part i on paper if you guys can , thanks.

http://papers.xtremepapers.com/CIE/...S Level/Mathematics (9709)/9709_s10_qp_11.pdf
Question 1) Explain, I read the answers but i don't get why

 

[CЯeScɘnt]

Can you go through that in detail please I still didn't get it?

do understand the term convergent?

 

[kitkat <3 :P]

I dont m doing the same question will u please explain it ?

do understand the term convergent?

 

[nishan2052]

ON paper 32 qn.6...plz help

 

[Browny]

do understand the term convergent?

Yes.

 

[CЯeScɘnt]

Browny kitkat <3 :P
0<1/3 tan*x>1

we want x to be subject

Multiplying by 3



0<tan*x>3

Taking under root

0< tanx>under root 3

Now tan inverse,tan inverse 0=0 and tan inverse under root 3= pi by 3
0<x>pi by 3

 

[kitkat <3 :P]

Thanks got it ^_^

Browny kitkat <3 :P
0<1/3 tan*x>1

we want x to be subject

Multiplying by 3



0<tan*x>3

Taking under root

0< tanx>under root 3

Now tan inverse,tan inverse 0=0 and tan inverse under root 3= pi by 3
0<x>pi by 3

 

[CЯeScɘnt]

Thanks got it ^_^

np

 

[Dudu]

http://papers.xtremepapers.com/CIE/...S Level/Mathematics (9709)/9709_w13_qp_13.pdf

Q 8 . iii)

Thanks if anyone could help me.

 

[Thought blocker]

http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Mathematics (9709)/9709_s09_qp_1.pdf

Question 10) i ii iii, with some brief explanations. i'd like to see part i on paper if you guys can , thanks.


http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Mathematics (9709)/9709_s10_qp_11.pdf

Question 1) Explain, I read the answers but i don't get why

2x^2− 12x + 13 We have to do complete square method.

10i)

so, 2(x^2 -6x) +13

2(x-3)^2+13

2(x^2-6x+9) +13

2x^2-12x+18 (to remove 18 subtract it from 18 and add 13)

2(x-3)^2 -5 hence, a = 2 b = -3 and c = -5


10ii)

graph has line of symmetry on x = 3 so you'll think that A should be 3, but see 2 is out the bracket so multiply it with 3 you get A as 6


10iii)

from eqn 2(x-3)^2 - 5 put x values as zero and 6, you get range is -5 to 13


1)