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...Fourier series solved problems phabala on find the for periodic extension of f t k odd numbers can be expressed as i to correspond indeces those we then have a rewrite resulting accordingly and since index is traditional pass from at end thus x cos b sin what sum this first draw function left apply jordan criterion according it converges all points where or rather its continuous discontinuity average result right which our e parameters period length frequency z dt tdt ak kt by parts h even bk werewritetheresulting akcos bksin whatis continuosu everywhere functions also an should get cosine did indeed given segment l after creating ipping shape about both axes eventually obtain with sine use special classical formulas in place has...