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Numerical Methods

            FORWARD DIFFERENCE OPERATOR                                  (a) 1                 (b) 2

            113.  The  values  of  a  function  f(x)  are                (c) 3                 (d) 4
                   tabulated below
                                                                                            [GATE-2017 (IN)]
                   x       0       1       2      3
                 f(x)      1       2       1      10
                   Using  Newton’s  forward  difference
                   formula,  the  cubic  polynomial  that
                   can be fitted to the above data, is


                          3
                                2
                                          2
                   (a) 2x +  7x −   6x +
                   (b) 2x −  7x +   6x −
                                2
                          3
                                          2
                        3
                               2
                   (c)  x − 7x −   6x + 1
                          3
                                2
                   (d) 2x −  7x +   6x + 1
                                            [GATE-2004]

            114.  The following table lists an nth order
                   polynomial
                                                  +
                                                        +
                                n
                    f  ( ) x = a x +  a x n− 1 + ..... a x a 0
                                     n−
                                                     1
                             n
                                       1
                    and    the     forward     differences
                   evaluated at equally spaced values of
                   x. The order of the polynomial is
               x      f(x)        f      2  f     3  f

                                 -
             -0.4  1.7648                0.089     -0.03
                              0.2965
                                 -                   -
             -0.3  1.4683                0.059
                              0.2075              0.0228
                                 -                   -
             -0.2  1.2608               0.0362
                              0.1485              0.0156
                                 -                   -
             -0.1  1.1123               0.0206
                              0.1123              0.0084
                                 -                   -
               0       1                0.0122
                              0.0917              0.0012
                                 -
              0.1   0.9083               0.011     0.006
                              0.0795

              0.2   0.8288  0.0685       0.017    0.0132




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