Page 34 - LAPLACE TRANSFORM
P. 34

Example   2






            By using the First Shifting Theorem determine the Laplace Transforms.
                        { }
                           at
                         te
                      L
                           f ( t = t
                           )
                                      1
                                 t
                       { (tf  } ) = L {}=
                                     s 2
                       ∴ { e at  f  (t ) =  at  •  } t
                                } { eL
                                        1
                                   =
                                     ( −  ) 2  2
                                      s








          Example   3




             By using the First Shifting Theorem determine the Laplace Transforms.

                              at
                       f ( t) = e sin bt

                                                     b
                       L   ( )}  =  L {sin bt }  =
                         { f t
                                                   2
                                                  s +  b 2

                              t
                                        at
                             ∴L  { fe at  ( )}  =  L { e sin bt }
                                         b
                                                      =  2  2
                                    (s −  ) a  + b











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