Page 117 - Schaum's Outline of Theory and Problems of Signals and Systems
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106                       LINEAR TIME-INVARIANT SYSTEMS                        [CHAP. 2




           2.47.  Compute the convolution sum  y[n] =x[nl* h[nl of the following pairs of sequences:







                 Am.  (a)  y[n] =             ns0
                                              n>O













           2.48.  Show that if  y(t) =x(t)* h(t), then
                                                       *
                                           yl(r) = ~'(r) h(r) =x(t) * hl(t)

                 Hint:  Differentiate Eqs. (2.6) and (2.10) with respect to  t.


           2.49.  Show that
                                                      *
                                                 ~(t) S'(1) =xt(t)
                 Hint:  Use  the result from Prob.  2.48 and Eq. (2.58).


           2.50.  Let  y[n] = x[n]* h[n]. Then show that

                                         x[n - n,]* h[n -n,]  = y[n -n, - n,]

                 Hint:  See Prob. 2.3.


           2.51.  Show that






                 for an arbitrary starting point  no.
                 Hint:  See Probs. 2.31  and 2.8.


           2.52.  The step response  s(t) of  a continuous-time LTI  system is given by



                 Find the impulse response  h(r) of  the system.
                 Am.  h(t) = S(t) - w,[sin  w,,flu(t)
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