Refer to Fig. 4-26 for the system with ideal C-to-D and D-to-C converters.(a) Suppose that...

Refer to Fig. 4-26 for the system with ideal C-to-D and D-to-C converters.

(a) Suppose that the discrete-time signal x[n] is

x[n] = 10cos(0.13πn. +π/13)

If the sampling rate is fs = 1000 samples/sec, determine two different continuous-time signals x(t) = x1(t) and x(t) = x2(t) that could have been inputs to the above system; i.e., find x1(t) and x2(t) such that x[n] = x1(nTs) = x2(nTs) if Ts= 0.001.

(b) If the input x(t) is given by the two-sided spectrum representation in Fig. P-4.12, determine a simple formula for y(t) when fs = 700samples/sec (for both the C-to-D D-to-C converters).