Page 17 - LAPLACE TRANSFORM
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1.3   Laplace Transform of a function by using Table (Linearity)



                       Example 3


                       Compute the following functions by using table of Laplace transform.

                                      -2t
                          1.  f(t) = t e
                                    4
                          2.  f(t) = t

                                      3t
                                          3  5t
                          3.  f(t) = 5e  + t e
                          4.  f(t) = 7t + 8 sin 6t


                                               2t
                                      3 -4t
                          5.  f(t) = 3 t e  + 4 e  cos 7t
                                              -2t
                                      2 3t
                          6.  f(t) = 5 t e  + 6 e  sin 7t + cos 8t





                       SOLUTION




                                          -2t
                              1.  f(t) = t e
                                                     -2t
                                       ʆ {f(t)}   = ʆ {t e }
                                                                                  1       1
                                                                             =         .
                                                  1                                         +  
                                            =
                                               (  +  ) 2
                                                                                1       1
                                                                           =        .
                                            =     1                                 2    +2
                                               (  +2) 2


                                                                                        1
                                                             -at
                         7  Exponent                       t e
                                                                                      (   +   ) 2













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