Mathematics: Post your doubts here!

[perpetuallystressed]

Need help! :-( http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Mathematics (9709)/9709_w11_qp_33.pdf

Q.6 (ii). I know how to get the radius but I can't figure out how to get the center of the circle?

 

[snowbrood]

Can you guys differentiate with respect to x ..
Q=
Sinx + Cosx
Sinx - Coxs

the answer is supposed to be 2 / Sin2x - 1


RoOkaYya G

http://sh.st/y4Fdw

 

[snowbrood]

I got it, Thank for your help =), can you help me this ? 32/0/n/11 question 7) iii)
http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Mathematics (9709)/9709_w11_ms_32.pdf

http://sh.st/y4FGr here you go

 

[Lily9605]

Need help! :-( http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Mathematics (9709)/9709_w11_qp_33.pdf

Q.6 (ii). I know how to get the radius but I can't figure out how to get the center of the circle?

I couldn't figure out the centre either..how did you get the radius?

 

[ali raza khan]

anyone please tell me the solution to question no. 1 ... i have my p3 exam tommorow.. please

 

[perpetuallystressed]

I couldn't figure out the centre either..how did you get the radius?

|w-w^2| is the diameter. So |-1+i-(-2i)| = (10)^0.5, and radius is 1/2 x (10)^0.5

 

[perpetuallystressed]

anyone please tell me the solution to question no. 1 ... i have my p3 exam tommorow.. please

lg10 (x+9)-lg10 (x) = 2
lg10 ((x+9)/x) = 2
x+9/x = 10^2
x+9 = 100x
x= 1/11

I have my P3 exam too...good luck!

 

[Lily9605]

|w-w^2| is the diameter. So |-1+i-(-2i)| = (10)^0.5, and radius is 1/2 x (10)^0.5

thank you so much! ] I'm also taking the exam tmr ! Good luck for tmr

 

[ali raza khan]

lg10 (x+9)-lg10 (x) = 2
lg10 ((x+9)/x) = 2
x+9/x = 10^2
x+9 = 100x
x= 1/11

I have my P3 exam too...good luck!

thanks alot dude i wish u best of luck too man

 

[ali raza khan]

anyone please tell me the solution to question no. 7 b ? please

 

[Anallia]

can someone please help with question 9b) http://papers.xtremepapers.com/CIE/...S Level/Mathematics (9709)/9709_w13_qp_33.pdf

 

[ali raza khan]

need some help with differiential equations

 

[RoOkaYya G]

Can you guys differentiate with respect to x ..
Q=
Sinx + Cosx
Sinx - Coxs

the answer is supposed to be 2 / Sin2x - 1


RoOkaYya G

s=sinx and c=cosx
using quotient rule :
u =s+c
du= c-s
v=s-c
dv=c+s

dy/dx = (vdu- udv) / v^2
=[(s-c)(c-s) - (s+c)(c+s)] / (s-c)^2

expand brackets
=[ (sc -s^2 - c^2 + sc) - (sc + s^2 + c^2 + cs) ] / (s-c) ^2

=(- 2s^2 -2c^2) / (s^2 +2sc+ c^2)
= 2/ 2sc+1
=2/sin2x +1

 

[Camille96]

Hello everyone, i just need a doubt cleared right away. My syllabus does not say anything about cross-product but it seems easy to use it when answering the vector problems. So i was worrying about whether cambridge allocates marks for when we use it because it's not in my syllabus? Also, can anyone give me a summary on complex numbers, please?

 

[RoOkaYya G]

need some help with differiential equations

cross multiply
2c^2 theta dx = 1 / 2c^2 theta
integrate on both side
(2x+1)^0.5 + c =0.5 tan theta

replace x=0 and theta =0.25 pi
u get c = -0.5
[ (2x+1) ^0.5 ] - 0.5 = 0.5 tan theta
(2x+1)^0.5= 0.5 tan theta + 0.5
= 0.5(tan theta +1)
(2x+1)= 0.25 (tan theta +1) ^2
x= 0.125 [ (tan theta +1)^2 ] - 0.5

 

[RoOkaYya G]

Hello everyone, i just need a doubt cleared right away. My syllabus does not say anything about cross-product but it seems easy to use it when answering the vector problems. So i was worrying about whether cambridge allocates marks for when we use it because it's not in my syllabus? Also, can anyone give me a summary on complex numbers, please?

http://www.physics.ohio-state.edu/~ntg/reu/pdf/complex_numbers.pdf
check this. its helpful. summarised complex notes

http://emedia.rmit.edu.au/learningl...rninglab/files/Complex Numbers_Polar Form.pdf

 

[Saad Amjad.]

do we need to use compass while drawing a circle in argand diagram..or just free hand??..please infrom kindly..im confused.

 

[Saad Amjad.]

cross multiply
2c^2 theta dx = 1 / 2c^2 theta
integrate on both side
(2x+1)^0.5 + c =0.5 tan theta

replace x=0 and theta =0.25 pi
u get c = -0.5
[ (2x+1) ^0.5 ] - 0.5 = 0.5 tan theta
(2x+1)^0.5= 0.5 tan theta + 0.5
= 0.5(tan theta +1)
(2x+1)= 0.25 (tan theta +1) ^2
x= 0.125 [ (tan theta +1)^2 ] - 0.5

do we need to use compass while drawing a circle in argand diagram..or just free hand??..please infrom kindly..im confused.

 

[Saad Amjad.]

http://sh.st/y4FGr here you go

do we need to use compass while drawing a circle in argand diagram..or just free hand??..please infrom kindly..im confused.

 

[RoOkaYya G]

do we need to use compass while drawing a circle in argand diagram..or just free hand??..please infrom kindly..im confused.

compass
no free hand.