1. The problem statement, all variables and given/known data The major problem I am facing while solving for fourier series is about the limits to be taken while integrating..!! In the general equation of fourier series the upper & lower limits are t1 & t1+T respectively..while solving for even functions we take t1 =-T/2..!! Why is it so..?? does this have something to do with the symmetry across y-axis?? In the 2 attached waveforms , in the first one , limits were like -pi to pi..while in 2nd limits are 0 to T/2.>!! I am not getting this..!! 2. Relevant equations 3. The attempt at a solution The limits are t1 to t1+T whre T is the time period..but I am not getting how to decide value of t1..!!