3.6 Consider sampling exactly three cycles of a continuous x(t) sinusoid resulting in an 8-point x(n) time sequence whose 8-point DFT is the X(m) shown in Figure P3-6. If the sample rate used to obtain x(n) was 4000 Hz, write the time-domain equation for the discrete x(n) sinusoid in trigonometric form. Show how you arrived at your answer. Figure P3-6 Real part of X(m) Imaginary part of X(m) 5.657 5.657 5 0 1 2 3 4 5 6 7 m 2 3 4 6 7 m -5.657