Page 42 - LAPLACE TRANSFORM
P. 42

Example   2







               Find the Laplace Transform using Multiplication by       of
                                                                                  

               the followings:-

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

                                     1
                           [ tf )(L  ]=       =n  1,
                                   s − a

                                               
                              at
                             e t.
                         L
                          { }  −=     d   1                                     Differentiate
                                        
                                      ds  − as  
                                             1   
                                   =  (− ) −     2 
                                        
                                          (s −  ) a  
                                        1
                                    =
                                     (s −  ) a  2








                                      f (x ) =  (s −  ) a  − 1


                                      f  ' (x ) =  −  ( 1 s −  ) a  − 1− 1  ) 1 ( =   −  ( 1 s −  ) a  − 2

                                                         =  −   1
                                                               (s −  ) a  2













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