Page 239 - Engineering Mathematics Workbook_Final
P. 239

Laplace Transforms

            57.    The  solution  of  the  differential
                   equation, for t > 0,

                     '' y  ( ) 2 't +  y  ( ) t +  y ( ) 0t =    with

                   initial conditions y(0) = 0 and y’(0) =
                   1,  is?  (u(t)  denotes  the  unit  step

                   function),

                            ( )
                          t −
                   (a) te u t
                          t −
                                   u
                   (b) (e −   te  t −  ) ( ) t

                        −
                                    u
                   (c) ( e +  t −  te  t −  ) ( ) t
                            ( )
                         t −
                   (d) e u t             [GATE-2016]

            58.    The Laplace transform of

                            n −
                                 t 
                    f  ( ) t = t e u ( ) t  is

                        (n +   ) 1 !              ! n
                   (a)         n+ 1      (b)         n
                          +
                                                +
                       (s    )              (s    )

                        (n −   ) 1 !               ! n
                   (c)         n+        (d)         n+ 1
                       (s    )  1           (s    )
                          +
                                                +

                                        [ESE-2018 (EE)]





























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