Page 160 - Schaum's Outline of Theory and Problems of Signals and Systems
P. 160

CHAP.  31   LAPLACE TRANSFORM AND CONTINUOUS-TIME LTI SYSTEMS



                 (b)  Applying the above property to signal xt(t) = du(t)/dt,  we obtain







                         Note that  Eq.  (3.46) can be  obtained by  continued application of  the  above  proce-
                     dure.


           3.33.  Verify Eqs. (3.47) and (3.481, that is,
                                    1
                 (a)  L-X(T) d~ ++ -X,(S)
                                    S




                 (a)  Let


                      Then

                      Now  if

                                                      dl) ++G,(s)
                      then by  Eq. (3.44)

                                              X1(s) =sG1(s) -g(O-)  =sGI(s)
                      Thus,









                 (b)  We can write





                      Note that the first term on the right-hand side is a constant. Thus, taking the unilateral
                      Laplace transform of  the above equation and using Eq. (3.47), we get







           3.34.  (a)  Show that  the  bilateral  Laplace  transform  of  x(t) can  be  computed  from  two
                      unilateral Laplace transforms.
                 (b)  Using  the  result  obtained  in  part  (a), find  the  bilateral  Laplace  transform  of
                      e-21rl.
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