Page 51 - Schaum's Outline of Theory and Problems of Signals and Systems
P. 51

SIGNALS AND SYSTEMS                             [CHAP.  1












           1.28.  Verify Eq. (1.30):




                     From  Eq. (1.28) we have





                 where  4(t) is a  testing  function which  is continuous at  t = 0 and vanishes outside some fixed
                 interval. Thus,  +I(!)   exists and is integrable over 0 < t < rn and  +(a) = 0. Then using Eq. (1.98)
                 or definition (1.18), we  have








                 Since 4(t) is arbitrary and by  equivalence property (1.991, we conclude that






           1.29.  Show that the following properties hold for the derivative of  6(t):





                 (6)  ts'(t) = -6(r)
                 (a)  Using Eqs. (1.28) and (1.201, we have


                                         00
                                           4(1)S.(t) dl = - /- m.(t)6(t) dl  = -4'(O)
                                        1- rn               - m
                 (b)  Using Eqs. (1.101) and (1.201, we have











                      Thus, by  the equivalence property (1.99) we conclude that
                                                      t6'(t) = -6(t)
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