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x
                                             x
               86.      (x – t) c–1 F a, b, c;1 –  y(t) dt = f(x).
                                             t
                      s
                     Here Φ(a, b, c; z) is the Gaussian hypergeometric function (see Supplement 10).
                        Solution:
                                     d n    a     x  (x – t) n–c–1  	         t
                                   –a
                            y(x)= x       x               F –a, n – b, n – c;1 –  f(t) dt ,
                                     dx n    s  Γ(c)Γ(n – c)                 x
                     where 0 < c < n and n =1, 2, ...
                        If the right-hand side of the equation is differentiable sufficiently many times and the
                     conditions f(s)= f (s)= ··· = f (n–1) (s) = 0 are satisfied, then the solution of the integral

                                    x           x
                     equation can be written in the form
                                          x  (x – t) n–c–1  	          t
                                  y(x)=              F –a, –b, n – c;1 –  f t (n) (t) dt.
                                         s  Γ(c)Γ(n – c)               x
                     •
                       Reference: S. G. Samko, A. A. Kilbas, and O. I. Marichev (1993).

               1.9. Equations Whose Kernels Contain Arbitrary
                      Functions

                 1.9-1. Equations With Degenerate Kernel: K(x, t)= g 1 (x)h 1 (t)+ g 2 (x)h 2 (t)
                       x

               1.       g(x)h(t)y(t) dt = f(x).
                      a
                                  1   d     f(x)     1           g (x)

                                                                  x

                     Solution: y =             =        f (x) –        f(x).
                                                         x
                                                                2
                                 h(x) dx g(x)    g(x)h(x)      g (x)h(x)
                       x

               2.       [g(x) – g(t)]y(t) dt = f(x).
                      a



                     It is assumed that f(a)= f (a)=0 and f /g ≠ const.
                                                     x
                                                        x
                                       d  x   f (x)

                                           x
                        Solution: y(x)=         .
                                       dx g (x)

                                           x
                       x

               3.       [g(x) – g(t)+ b]y(t) dt = f(x).
                      a
                     Differentiation with respect to x yields an equation of the form 2.9.2:
                                                 1        x       1


                                           y(x)+  g (x)   y(t) dt =  f (x).
                                                                    x
                                                   x
                                                 b                b
                                                        a
                        Solution:                          x
                                         1        1              g(t) – g(x)

                                   y(x)=   f (x) –  g (x)  exp           f (t) dt.


                                                                          t
                                            x
                                                    x
                                         b       b 2     a         b
                       x

               4.       [Ag(x)+ Bg(t)]y(t) dt = f(x).
                      a
                     For B = –A, see equation 1.9.2.
                        Solution with B ≠ –A:
                                       sign g(x) d         –  A     x       –  B
                                 y(x)=               g(x)   A+B    g(t)   A+B  f (t) dt .

                                                                           t
                                        A + B dx              a
                 © 1998 by CRC Press LLC
                © 1998 by CRC Press LLC
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