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Numerical Methods

            101.  Numerical         integration      using               (a) h                 (b) h
                                                                                                    3
                                                                              2
                   trapezoidal  rule  gives  the  best  result
                                                                                                    5
                                                                              4
                   for  a  single  variable  function,  which            (c) h                 (d) h
                   is
                                                                                            [GATE-2009 (PI)]
                   (a) linear            (b) parabolic                                                      −
                                                                  105.  The differential equation    dx  =  1 x
                   (c) logarithmic       (d) hyperbolic                                              dt      
                                                                         is discretised using Euler’s numerical
                              [GATE-2016-ME-SET II]
                                                                         integration  method  with  a  time  step
            102.  P(0,  3),  Q  (0.5,  4)  and  R  (1,  5)  are            T   0.  What  is  the  maximum
                                                                                                 
                   three points on the curve defined by                  permissible  value  of  T   to  ensure
                   f(x). Numerical integration is carried                stability  of  the  solution  of  the
                   out  using  both  Trapezoidal  rule  and              corresponding discrete time equation?

                   Simpson’s  rule  within  limits  x  =  0
                                                                                                  
                   and  x  =  1  for  the  curve.  The                   (a) 1                 (b)  /2
                   difference  between  the  two  results                (c)                  (d) 2
                   will be
                                                                                                 [GATE-2011]
                   (a) 0                 (b) 0.25
                                                                  106.  The  ordinary  differential  equation
                   (c) 0.5               (d) 1                            dx  = − 3x + , with x (0) = 1 is to be
                                                                                      2
                         [GATE-2017 ME SESSION-I]                         dt
                                                                         solved  using  the  forward  Euler
                 FORWARD EULER METHOD                                    method. The largest time step that can

                                              du                         be used to solve the equation without
            103.  Consider  the  equation        =  3t +  2  1           making     the    numerical    solution
                                              dt                         unstable is ________.

                   with  u  =  0  at  t  =  0.  This  is
                   numerically  solved  by  using  the                                [GATE-2016-EC-SET 2]
                   forward  Euler  method  with  a  step
                   size.  t  =  2.  The  absolute  error  in     107.  Variation  of  water  depth  (y)  in  a
                   the  solution  in  the  end  of  the  first           gradually varied open channel flow is
                   time step is _____.                                   given  by  the  first  order  differential
                                                                         equation
                                            [GATE-2017]
                                                                                            − 10 ln y
                                                                                        −
            104.  During  the  numerical  solution  of  a                      dy  =   1 e   3
                                                                                         −
                   first order differential equation using                     dx   250 45e    − 3ln y
                   the  Euler  (also  known  as  Euler                   Given initial condition y (x = 0) = 0.8
                   Cauchy) method step size h, the local                 m.  The  depth  (in  m,  up  to  three
                   truncation error is of the order of



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