[CIE] All Pure Mathematics (P1, P2 and P3) doubts here !

[SkyPilotage]

Yup, and the angle between them will be zero.

thanks..

[Tohru Kyo Sohma]

-If you want to plot the point of the line just substitute x with any value from 0 to pi. ex  0.25pi+2y=pi--->0.75pi=2y find y and u have a point....
Do the same for another value of x and u get another point then join them to draw the line...
-Regarding the signs you put them on a number line and put the values on the number...outside the range of values is the same sign as a(coefficiient of x^2)....
for example if you have : x^2-x<0 so u put in the number line x=0 and x=1 soo outside this range is +ve since x^2 is +ve and inside the range is -ve. Since the question asks for <0 (-ve) it is 0<x<1. I hope that helps.   

i still didnt get question number 2 ......can u like solve it a take a picture and upload it....i think if i see it i can understand better!!

[SkyPilotage]

i still didnt get question number 2 ......can u like solve it a take a picture and upload it....i think if i see it i can understand better!!

'
yh i know but i dont have a scanner so we will have to wait for someone else to upload the pic ..

[Tohru Kyo Sohma]

'
yh i know but i dont have a scanner so we will have to wait for someone else to upload the pic ..

i think i kind of got the answer but im still not sure if the graph is right..its ok!

[iluvme]

Here you go.

[haris94]

how will u differentiate         
12/x²-4x

[........]

how will u differentiate         
12/x²-4x

http://www.wolframalpha.com/input/?i=Differentiate+12%2F%28x^2-4x%29

[haris94]

thanx got it
cool website By the way

[physichemaths]

http://www.xtremepapers.me/CIE/International%20A%20And%20AS%20Level/9709%20-%20Mathematics/9709_w10_ms_12.pdf

question 5 (b) how we know that we use the formula a(1-r^n)/1-r? why not we use a(r^n-1)/r-1??

[elemis]

http://www.xtremepapers.me/CIE/International%20A%20And%20AS%20Level/9709%20-%20Mathematics/9709_w10_ms_12.pdf

question 5 (b) how we know that we use the formula a(1-r^n)/1-r? why not we use a(r^n-1)/r-1??

Both formulas are the same thing, you can use either.

[Tohru Kyo Sohma]

Here you go.

thanx alot amii

[Tohru Kyo Sohma]

i just have a few more questions...pls pls help me...its;
1. may/june 2009 p1 qns 4 part 2....the answer is 7pi/12....but i cant get it right....can some one show how?
2. oct/nov 2009 p12 qns 5 part 1 ,can someone show me how to solve the inequality?
3. oct/nov 2010 p12 qns 7 part 3....
4. oct/nov 2010 p13 qns 8 part 2 ?
PLEASE HELP ME...!!!!!EXAM TOMORROW!!

[elemis]

Question 1

6 sin(2x) +3 = 0

sin(2x) = -1/2

sin^-1(-1/2) = -30, 330, 690, 210 or 570.       I prefer working in degrees then converting to radians at the end.

Dividing all the above answers by 2.

-15, 165, 345,105, 285.

-15 is not in the given range (see question), hence, we ignore it.

The smallest angles is thus 105 degrees. Converting to radians give the correct answer.

Question 2

Part 1 :-  Expanding :

sinx -sin²xcosx +cosx -sinxcos²x

Substitute cos²x for sin²x and sin²x for cos²x. You should get the answer.

Part 2 :-

cos³x = 8sin³x







Solve for x.

Question 3

I'll get back to you on this one.

[Tohru Kyo Sohma]

Question 1

6 sin(2x) +3 = 0

sin(2x) = -1/2

sin^-1(-1/2) = -30, 330, 690, 210 or 570.       I prefer working in degrees then converting to radians at the end.

Dividing all the above answers by 2.

-15, 165, 345,105, 285.

-15 is not in the given range (see question), hence, we ignore it.

The smallest angles is thus 105 degrees. Converting to radians give the correct answer.

Question 2

Part 1 :-  Expanding :

sinx -sin²xcosx +cosx -sinxcos²x

Substitute cos²x for sin²x and sin²x for cos²x. You should get the answer.

Part 2 :-

cos³x = 8sin³x







Solve for x.

Question 3

I'll get back to you on this one.

thanx alot!

[SkyPilotage]

i just have a few more questions...pls pls help me...its;
1. may/june 2009 p1 qns 4 part 2....the answer is 7pi/12....but i cant get it right....can some one show how?
2. oct/nov 2009 p12 qns 5 part 1 ,can someone show me how to solve the inequality?
3. oct/nov 2010 p12 qns 7 part 3....
4. oct/nov 2010 p13 qns 8 part 2 ?
PLEASE HELP ME...!!!!!EXAM TOMORROW!!

Question 3:
Complete the square of f(x) to get (x-2)^2+3 to H(x-2)=(x-2)^2+3----> so H(x) = x^2+3.....
Question 4:
length of PQ is the (length of radius of the arc - height of triangle ) x 2
----> (5-5cos(0.6rad))x2


@ Ari: do you know how marks are distributed on sketches of graphs? (not drawings)