(a) Consider the signal5sin (15t – 60°) + 2 sin (7t)If this signal is periodic, find its f...

(a) Consider the signal

5sin (15t – 60°) + 2 sin (7t)

If this signal is periodic, find its fundamental period T0 and its fundamental frequency ω0. Otherwise, prove that the signal is not periodic.

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(b) Repeat Part (a) for the signal

x(t) = cos (πt) + 5e–j15t + sin(7t)

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(c) Repeat Part (a) for the signal x(t) = sin (pt) + cos (3t)

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(d) Repeat Part (a) for the signal x4(t) = x1(t) + x2(t) + x3(t), where