Hello, I'm having some trouble completing a Fourier series question.
We have f(x)=Cos(x), for abs(x)≤π/2
f(x)=0, for π/2≤abs(x)≤π
period=2π
and then show that the Fourier series f(x) reads
http://img71.imageshack.us/img71/3424/84335314oi1.jpg
now I can get the 1/π and the...