on my graphical calculator it's: F4, F6, F1 then the integral comes up and you can type in your values. However it can only be used for checking you have the correct answer as I can't find a way to make the answer "exact" (i.e. it never has ln in the answer).

Reply 1587

Dilzo999

19

Original post by rambo1168

ImageUploadedByStudent Room1403088776.859436.jpg

how would u integrate this

Posted from TSR Mobile

You can although you probably won't be able to, this is the answer:

Reply 1588

Tuya

4

Original post by Undisclosed 15

How do you integrate (cosx)^3?

Posted from TSR Mobile

Obviously you use de Moivres theorem to work it out in terms of cos(nx) and then integrate. Simples.

Reply 1589

DocdoLITTLE

1

Original post by sarchi

I dunno could you maybe start with this? Correct me if I'm wrong pls

Posted from TSR Mobile

I THINK YOU ARE OVER COMPLICATING IT.

THIS IS WHAT I WOULD DO.

U = 2-X^5

DX= DU/-5X^4

INTGRAL OF SINU(DU/-5X^4)

TAKE 1/-5X^4 OTHER SIDE OF THE INTEGRAL BECAUSE IT IS A CONSTANT. AND INTEGRATE SINU WITH RESPECT TO U.

once you have finished sub in value of u into answer and multiply by 1/-5x^4

i may be wrong though..have you got the answer?

Reply 1590

Light_bulb

8

Original post by Dilzo999

You can although you probably won't be able to, this is the answer:

How'd would we even go about this maybe using the Gaussian hypergeometric function?

Reply 1591

sarchi

Original post by Light_bulb

The answer to this is complex, you can't do it using the method you did they won't ask a trig function to a non linear bracket

oh okay cool thnx

Reply 1592

Mr.Obsessed

11

Original post by Light_bulb

You come to a "loop" when you can add the two like integrals, hence why you divide the answer by 2 at the end.

Could you do the question for me as an example? :colondollar:

Reply 1593

Dilzo999

19

Original post by DocdoLITTLE

I THINK YOU ARE OVER COMPLICATING IT.

THIS IS WHAT I WOULD DO.

U = 2-X^5

DX= DU/-5X^4

INTGRAL OF SINU(DU/-5X^4)

TAKE 1/-5X^4 OTHER SIDE OF THE INTEGRAL BECAUSE IT IS A CONSTANT. AND INTEGRATE SINU WITH RESPECT TO U.

once you have finished sub in value of u into answer and multiply by 1/-5x^4

i may be wrong though..have you got the answer?

That's wrong.

Reply 1594