Hi experts,

How does one solve

I have attempted to use the identity cos^2x=1/2(1+cos2x) to give

However I am not sure how to proceed any further because of the double angle....

In another attempt, i tried tackling it using the method of substitution such as below

let u=cosx then du = -sinxdx

then

But this answer doesnt look right either....

Any tips or suggestions on what I am doing wrong will be appreciated. Thanks

Bugatti