Mathematics: Post your doubts here!

[Minato112]

help
minato112
whitecorp

Srry but havent done vectors yet.

 

[PhyZac]

PhyZac
Here are the answers
Srry for the handwriting though

Oh okay Jazaka Allah khairan...I got it

 

[parthrocks]

help
minato112
whitecorp

nightrider1993

 

[parthrocks]

nightrider1993

http://www.xtremepapers.com/community/attachments/untitled-png.16447/

 

[nightrider1993]

http://www.xtremepapers.com/community/attachments/untitled-png.16447/

Just use the cosine rule for part a:
cos x = ( (A)(B) )/ (mod(A)*mod(B)) where A= displacement vector of first plane and B= displacement vector of second plane

 

[nightrider1993]

http://www.xtremepapers.com/community/attachments/untitled-png.16447/

For second part use help from following site. I would hv done it bt im abit busy
http://members.tripod.com/vector_applications/xtion_of_two_planes/index.html

 

[SalmanPakRocks]

Oct/Nov 2009 Q8
The first term of an arithmetic progression is 8 and the common difference is d, where d is not equals to 0. The first term, the fifth tern and the eight term of this arithmetic progression are the first term, the second term and the third term, respectively, of a geometric progression whose common ratio is r.
(i) write down two equations connecting d and r. Hence show that r = 3/4 and find the value of d. [6]

 

[iKhaled]

Oct/Nov 2009 Q8
The first term of an arithmetic progression is 8 and the common difference is d, where d is not equals to 0. The first term, the fifth tern and the eight term of this arithmetic progression are the first term, the second term and the third term, respectively, of a geometric progression whose common ratio is r.
(i) write down two equations connecting d and r. Hence show that r = 3/4 and find the value of d. [6]

u need help in this question or what..?

 

[Minato112]

Oct/Nov 2009 Q8
The first term of an arithmetic progression is 8 and the common difference is d, where d is not equals to 0. The first term, the fifth tern and the eight term of this arithmetic progression are the first term, the second term and the third term, respectively, of a geometric progression whose common ratio is r.
(i) write down two equations connecting d and r. Hence show that r = 3/4 and find the value of d. [6]

Here are the answers bro
Hope it helps.
(And srry for the handwriting! )

 

[Shahed Shubeir]

a stone is dropped from the top of a building of a hight 20m. Find the time it takes to reach the ground and the velocity with which it hit's the ground.


can Any1 , help in this question?

 

[Minato112]

a stone is dropped from the top of a building of a hight 20m. Find the time it takes to reach the ground and the velocity with which it hit's the ground.


can Any1 , help in this question?

No more informations are given?

 

[SalmanPakRocks]

u need help in this question or what..?

Why else would I post an entire question here then?

 

[SalmanPakRocks]

Here are the answers bro
Hope it helps.
(And srry for the handwriting! )

Thank you so much!

 

[Minato112]

Thank you so much!

No prob!

 

[GorgeousEyes]

a stone is dropped from the top of a building of a hight 20m. Find the time it takes to reach the ground and the velocity with which it hit's the ground.


can Any1 , help in this question?

a stone is dropped from the top of a building of a hight 20m. Find the time it takes to reach the ground and the velocity with which it hit's the ground.


can Any1 , help in this question?

a=10
u=0 ( dropped ---> initial velocity is = 0 )
s=20 cm
t=?

Okay . . you have a and u and s and you r searching for t , so u will use s=ut+1/2 atsquare .
20=1/2 10 tsquare .
So by solving it :
t=2 .
Now you need velocity : final velocity , you have a , u and s and you want v , so u will use : vsquare = usquare +2as
vsquare=(0)square +2x10x20
so v= 20
Hope you understood it

 

[Rai289]

Hey guys,

I really need help with question 5 of the following paper:

http://www.xtremepapers.com/papers/...S Level/Mathematics (9709)/9709_w10_qp_13.pdf

I've looked at the answers and still couldn't figure it out :/ Both parts please, any help would be greatly appreciated.

Thanks in advance.

 

[Just visiting]

I need help urgent plz.....http://www.xtremepapers.com/papers/...S Level/Mathematics (9709)/9709_w10_qp_42.pdf
Question 3 i dont understand how did he solve it. Plz make explanation clear

 

[hussamh10]

No more informatVions are given?

2as=v^2-u^2
U=o
and a=10
s is given so iguess u can find out now

 

[iKhaled]

Hey guys,

I really need help with question 5 of the following paper:

http://www.xtremepapers.com/papers/CIE/Cambridge International A and AS Level/Mathematics (9709)/9709_w10_qp_13.pdf

I've looked at the answers and still couldn't figure it out :/ Both parts please, any help would be greatly appreciated.

Thanks in advance.

for 5 (i)... differentiate the given equation and dy/dx= -1(x-3)^-2 + 1 and d^2y/dx^2 = 2(x-3)^-3

for 5(ii) we need to find the x coordinates for both the stationary A and B and uk that dy/dx represents the gradient of the curve and for any stationary point the gradient is equal to 0 so,

0 = -1(x-3)^-2 + 1
x = ±1 + 3
x = 4
x = 2

now we should find if either x=4 is a minimum point or x = 4 is a maximum point and same goes to x=2 and we do that by using the second derivative

the value of d^2y/dx^2 at x = 4 is bigger than zero which means it is a minimum point and at x = 2 the value of d^2y/dx^2 is smaller than zero which means at x=2 the point is maximum

so A is ( 2, 0 ) and B is ( 4, 5 ) i hope u got it !!

 

[panda222]

I think i may have found a mistake in the mark scheme.

Question 3 on Oct/Nov 2010 Qp 12

http://www.xtremepapers.com/papers/CIE/Cambridge International A and AS Level/Mathematics (9709)/9709_w10_qp_12.pdf

The mark scheme doesn't multiply the dx/dt by the power of the bracket.

Link to mark scheme:

http://www.xtremepapers.com/papers/CIE/Cambridge International A and AS Level/Mathematics (9709)/9709_w10_ms_12.pdf

I need help on this ASAP.

EDIT: Guys i need help with this ASAP, exam's tommorow.

iKhaled
hussamh10
minato112
nightrider1993