HELLO,

I d be grateful to anyone who solves the following, as I have been trying for ages but it is not working.

Q/ solve by finding appropriate substitution and then integrate by parts:

integral of cos(sqrt x).

Thanks.

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- Aug 3rd 2009, 06:08 AMfadeercos(sqrt x)
HELLO,

I d be grateful to anyone who solves the following, as I have been trying for ages but it is not working.

Q/ solve by finding appropriate substitution and then integrate by parts:

integral of cos(sqrt x).

Thanks. - Aug 3rd 2009, 06:22 AMCaptainBlack
- Aug 3rd 2009, 06:29 AMfadeer
I am sorry but could you make it a little clearer.

Thanks. - Aug 3rd 2009, 06:37 AMCaptainBlack
If $\displaystyle u=\sqrt{x}$ we have:

$\displaystyle

\int \cos(\sqrt{x})\; dx=\int \cos(u) \frac{dx}{du}\;du=2 \int u\cos(u)\;du

$

and now you use integration by parts.

(If you need more help WolframAlpha will give you a step by step explanation of the complete process)

CB - Aug 3rd 2009, 06:45 AMfadeer
Thanks a lot bro,

No need bcz I know to complete it.

I was stuck with the substitution part.

I appreciate ur help.