A continuous time system, described by y(t) = 5 Cos (2*?*20*t + ?/2), is sampled at a rate 320 Hz.
(a) Write the mathematical expression that describes the discrete time (sampled) signal.
(b) Calculate the value of the discrete signal for n = 0 and n = 4.
(c) Does the sampling rate meet the Nyquist condition?