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n
                                          k
                     3 .For g(x)=   A k (ln x) , a solution of the equation has the form
                      ◦
                                 k=0
                                                        n
                                                                 k
                                                 y(x)=    B k (ln x) ,                      (3)
                                                       k=0
                     where the constants B k can be found by the method of undetermined coefficients.

                                  n
                     4 .For g(x)=   A k cos(λ k ln x), a solution of the equation has the form
                      ◦
                                 k=1
                                             n                n

                                      y(x)=    B k cos(λ k ln x)+  C k sin(λ k ln x),       (4)
                                            k=1               k=1

                     where the constants B k and C k can be found by the method of undetermined coefficients.
                                  n
                     5 .For g(x)=   A k sin(λ k ln x), a solution of the equation has the form
                      ◦
                                 k=1
                                             n                n

                                      y(x)=    B k cos(λ k ln x)+  C k sin(λ k ln x),       (5)
                                            k=1               k=1
                     where the constants B k and C k can be found by the method of undetermined coefficients.
                        Remark. A linear combination of eigenfunctions of the corresponding homogeneous
                     equation (see 4.9.59) can be added to solutions (1)–(5).


               4.10. Some Formulas and Transformations

                   Let the solution of the integral equation

                                                  b

                                          y(x)+    K(x, t)y(t) dt = f(x)                    (1)
                                                 a
               have the form
                                                        b
                                          y(x)= f(x)+   R(x, t)f(t) dt.                     (2)
                                                      a
               Then the solution of the more complicated integral equation

                                               b       g(x)

                                        y(x)+    K(x, t)   y(t) dt = f(x)                   (3)
                                               a       g(t)
               has the form

                                                     b      g(x)
                                        y(x)= f(x)+   R(x, t)   f(t) dt.                    (4)
                                                    a       g(t)
               Below are formulas for the solutions of integral equations of the form (3) for some specific func-
               tions g(x). In all cases, it is assumed that the solution of equation (1) is known and is given
               by (2).




                 © 1998 by CRC Press LLC









               © 1998 by CRC Press LLC
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