Page 20 - LAPLACE TRANSFORM
P. 20

A                                   B         1            
                                                   1                   =        .    2      2
                                    =          .                            −         +   

                                                   +  
                                                                            1  .        
                                =      3!    .   1                     =    −2       + 7   2
                                                                                     2
                                          3+1    +4


                                            = 3 [   3!   ]  + 4 [     −2   ]
                                                                    2
                                                 (  +4) 3+1     (  −2) + 7 2
                                            = 3 [ 1  2  3  ]  + 4 [     −2   ]
                                                                  2
                                                 (  +4) 4     (  −2) + 49
                                                18         4  −8
                                            =          +
                                                             2
                                               (  +4) 4  (  −2) + 49

                                                               e  (n = 1,2,3 … . )
                                                     1      t n-1  -at                        1
                         8  Exponent
                                                   (n−1)!
                                                                                            (   +   )   

                                                         n  -at
                         9  Exponent                   t  e  (n = 1,2,3 … . )                   !
                                                                                           (   +   )   +1


                                                                                           (s + a)
                                                               -at
                        13  Decaying cosine                  e   cos ωt
                                                                                      (s + a) + ꞷ     2
                                                                                               2






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

                                                    A        B
                                                   2 3t
                                                            -2t
                                      ʆ {f(t)}   = ʆ {5 t e  + 6 e  sin 7t + 2 cos 8t}


                                            = 5 [     !   ] + 6 [         ] + 2 [       ]
                                                                                2
                                                                    2
                                                 (  −  )   +1  (  +  ) +    2     +    2










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