Page 51 - LAPLACE TRANSFORM
P. 51

f(t) =         +       +       =        +       +    
                             (  +3) 1  (  +3) 2  (  +3) 3  (  +3) 1  (  +3) 2  (  +3) 3


                                                   =  (        ) + 6 (       )
                                                       (  +3) 2     (  +3) 3
                                                        -3t
                                                                       e
                                                   =  t e  + 6   1  t 3-1  -3t
                                                               (3−1)!
                                                        -3t
                                                   =  t e  +     t e
                                                                 2  -3t











                                      s  + 8
                          F
                       4.   (s ) =
                                 ( +  ) 5  2 ( +  ) 4
                                  s
                                         s










                                                                                                   
                                                                   
                                                               s + 8   = A (   +   ) (   +   ) + B (   +   ) + C(   +   )


                              when s= − 5;

                                                                  
                                                                                                  
                                                s + 8 = A (   +   ) (   +   ) + B (   +   ) + C(   +   )
                                            − 5 + 8 = B (− 5 + 4)

                                                          = − 3


                              when s= − 4;

                                                                                               2
                                                               1
                                            s + 8   = A (   + 5) (   + 4) + B (   + 4) + C(   + 5)
                                                                2
                                                          − 4 + 8   = C(−4 + 5)
                                                         =   






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