In your guys opinion, what is the best way to compute that kind of integral?

or

That integrals apperars when we´re calculating the coefficients of Fourier Series, and i guess there´s a "general" way to solve them.. Can someone help me?

Thanks!

[Im new here at this forum, im using FF3.0.9+GreaseMonkey+TexTheWorld to write in TeX here.]