I read in a reference book by Schuler/Fowler about Harmonics. they had given that we can generate any waveform adding two sine waves. they have constructed a sawtooth signal using the odd & even with fundamental harmonics. my question is have they constructed it by vector addition of the harmonics or any other method.(they have taken fundamental to 9th harmonic ) can you please explain the method they must have used for constructing the saw tooth signal.