Let x[n] be a real, causal, finite-length sequence with length N = 4 that is also period...

Let x[n] be a real, causal, finite-length sequence with length N = 4 that is also periodically causal. The real part of the 4-point DFT X_R[k] for this sequence is shown in Figure P12.19. Determine the imaginary part of the DFT jX_I[k].