Hi all,

I've got a bit of a problem with this question, if anyone could show the working it would be appreciated. I've got the suspicion it's meant to be done via substitution, but looking to learn.

$\displaystyle \int^{\pi/8}_0 (\theta + \cos4\theta) d\theta$

I'm pretty sure that the answer is (32 + pi^2) / 128 but of course, the answer isn't everything.

Anyone able to help me out? Cheers.