I have got some question here.
Find the fourier series for f(x)= x + pi at -pi to + pi and also f(x + 2pi)= f(x).
Find the second harmonics.
May i know if this question is juz asking us to find a0, an and bn?
Or we need to find out whether it's a odd or even function?
Pls advise.
Thanks.

 

Finding if it is odd or even or half-way symmetric, just gives you some insight into what An and Bn can be. It is not absolutely neccessary to determine the symmetry, but it can save some work.