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2.2  THEOREM 2 : THE FIRST SHIFTING THEOREM





        The  first  shifting  formula  states  that  f(s)  is  the  Laplace  Transform  of  f(t),  where ‘a’  is  a
        constant. We obtained F(s+a) by replacing every ‘s’ in F(s) by  ‘s+a’. The variable ;s; has been
        shifted by amount ' a'












           Example   1






             By using the First Shifting Theorem determine the Laplace Transforms of

            the followings.



                     { }
                       at
                      e
                   L


                          at
                       Let e =  e at  1 .    so   f  ( ) 1=t

                       L  { tf ( )}    =    L   ) 1 (      =  1
                                               s


                                                   e
                                      t
                                                     at
                       Hence L   { e at  f ( )}     =     L    { .  } 1

                                              1
                                           =
                                             s −  a






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