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Differential and Integral Equation




                    Notes                     2
                                           dz    z  l
                                                   .
                                           d     a

                                             l
                                           z  ( /2 1)
                                                       , c
                                             l
                                          1 ( /2)   a
                                           1   1 ( /2)  aY X      x m  1   y n  1
                                                l
                                              z             c             a      . c
                                          2 l           a         ( a m  1)  n  1

                                                        2
                                                              2
                                                           2
                                          Example 5: Solve: z  (p  + q  + 1) = c 2
                                   Solution:
                                                   z 2
                                   Put z dz = dZ i.e. Z =
                                                    2
                                           Z   dZ  Z
                                                 .   = zp = P (say)
                                           x   dz  x

                                           z   dZ   z
                                                      = zq = Q (say)
                                           Y    z   Y
                                          The given equation becomes
                                               2
                                                   2
                                          2Z + P  + Q  = c 2
                                   now let Z = f (x + ay) + f (X)
                                              Z   dZ  X  dP
                                          P =       .
                                              x   X   x  dx
                                               Z  dZ  X    dZ
                                          Q =       .    a
                                              Y    X  y    dX

                                           dZ  2
                                                    2
                                                        2
                                               (1 + a ) = c    2Z
                                           dx
                                          dZ  (1 a 2 )
                                   or        2   2   dx
                                            (c  a  ) z

                                                 2
                                                      2
                                   or        [(1 + a )]  [(c    2Z)] = X + c
                                                    2
                                                 2
                                                        2
                                   or        (1 + a )  (c    z ) = (x + ay) + c
                                                    2
                                              2
                                                 2
                                                                2
                                   or     (1 + a ) (c    z ) = (x + ay + c) .
                                   Self Assessment
                                   Solve
                                             2
                                   14.  p (1 + q ) = q(z   a)
                                        2
                                            2
                                   15.  p  = z  (1   pq)

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