1. The problem statement, all variables and given/known data What is the percentage of power (out of the total power) contained up to the third harmonic (power in DC component, a1 , a-1 , a2 , a-2 , a3 , a-3 ) of the square waveform shown above? (the duty cycle = D = τ/T0= 0.5) 2. Relevant equations 3. The attempt at a solution Hey all, The following question refers to the attached diagram. I thought the question was simple enough due to the amplitude being 1, and the value of D being 0.5. The simplified formula I calculated for the answer is 2/(k*pi) for odd harmonics (as even values of k result in a value of 0) -However when adding 2/pi and 2/(3*pi) i get 0.8488 and hence 84.9% However the multiple choice answers are 96.7, 95, 72.5 and 73.3% I am not sure whether this is a simple mistake or a large misunderstanding of the theory. Any help would be much appreciated!