Integration help

Zoe-b

Homework Statement

Part of a question has brought up this problem:

find the integral of cos(n arcsin x) * xm dx
where n and m are positive integers > 1.

Homework Equations

Not sure- if the n wasn't there I would simplify it to (1-x2)1/2 * xm which would make it easier but as it is I'm not sure how to proceed.
Using a maths programme I have it seems to be able to integrate it only if n is even.. but I have no idea why this is or how to get to the answer.

The Attempt at a Solution

Haven't got very far at all as you can see, sorry.
I already did a substitution from cos(u) * cos (nu) * (sin u)m du to the above where x = sin u.