Express each of the following periodic signals by its Fourier series in all three forms, identify the time period and the harmonics present, compute the signal power and the value, and, for parts (a) and (b), sketch the one-sided and two-sided spectra.

a) x(t) = 4 + 2 sin (4 pi t + pi/4) + 3 sin (16 pi t) + 4 cos (16 pi t)

b) x(t) = sigma_k = -4_k notequalto 0^4 6/k sin (k pi/2) e^-j k pi/3 e^j k 6 pi t

c) x(t) = 2 - 4 cos (8 pi t + 0.25 pi) + 10 sin (12 pi t - pi/3)