This one can be a little tricky. Use integration by parts.

Let

Therefore:

Let

The integral portion becomes

Can you finish up now?.

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- Jul 30th 2006, 03:50 AM #1

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## I need help again!

Okay, this question is making me confused.

(i) State the derivative of sin(x^2).

I got that correct but I can't get the next part.

(ii) Find (integrate) x^3 cos (x^2) dx.

Answer: 1/2 [x^2 sin (x^2) + cos (x^2)] + C.

Thanks in advance if you could help!

- Jul 30th 2006, 04:57 AM #2

- Jul 30th 2006, 05:49 AM #3

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- Jul 30th 2006, 07:36 AM #4

- Jul 31st 2006, 04:20 AM #5

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