Find a Fourier series expansion of the periodic function Select one: f(t) = {37 cost f(t)=f(t+2x) 0 f(t)=6+62 f(t)=3+6 d. f(t)=3+6 00 0 00 P2=1 7=1 a. (t)=6+6(1)* cos nt 2n-1 n=1 -asts. T Sts. sts Sta (-1)* cosnt 2n-1 77+1 (-1) cos 2nt 4n. -1 -T (-1)" cos 2nt 2 4n-1 1