FOURIER SERIES WAVEFORM ANALYSIS
CASE -1: When both positive and negative waveforms are equal then the signal is symmetric about x axis. In this case a0=0 CASE -2: When the waveform is folded with respect to x(vertical) axis.After folding this waveform remains same. In this case bn=0 CASE -3: When the waveform(right of left) is folded with respect to y(horizontal) axis. Then the already folded waveform is folded with respect to x(vertical axis).Then the waveform must remain same for folded waveform and unfolded waveform. In this case an=0