Page 55 - LAPLACE TRANSFORM
P. 55

0  = A + B  ............................... (1)
                                     − A  = B,
                                         B  = −A =  −   
                                                       


                                        5 = 41A + 2C ......................... (3)
                                                               3
                                                                    2
                                         2C = 5 − 41A = 5 − 41( ) =
                                                              25   25
                                                      
                                           C =         2    =
                                             2 (25)      



                              f(t)    =        +       +  
                                               2
                                          +2  s +10  +41


                                                       1
                                                 3
                                         3    (− )    + ( )
                                     =    25  +   25   25
                                                2
                                          +2   s +10  +41


                                         3     1   ( −3  +1 )
                                     =    25  +  25
                                               2
                                          +2   s +10  +41


                                             1            −3  +1
                                     =     {   } +     {          }
                                                             2
                                                +2        (s+5) +4 2
                                                                       (-3s -15) + 16 = -3s + 1

                                        3  -2t      1  −3(  +5) + 16
                                     =    e       +   {            }
                                                             2
                                       25          25   (s+5) +4 2


                                        3          1   −3(  +5)        16
                                           -2t
                                     =    e      +   {          +           }
                                                           2
                                                                       2
                                       25         25   (s+5) +4 2  (s+5) +4 2


                                                   1
                                           -2t
                                     =  3   e      +   { −3(  (  +5)   ) +  4(   4  ) }
                                                               2
                                                                              2
                                        25        25       (s+5) +4 2     (s+5) +4 2


                                       3
                                                 1
                                                                        -5t
                                           -2t
                                                         -5t
                                     =   e     +   { −3e         4   + 4e  Sin 4t }
                                       25        25


                                                   
                                                                   
                                         
                                                                    -5t
                                           -2t
                                                    -5t
                                     =   e   −   e              +   e  Sin 4t
                                                                    





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