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x

                                  2    2
               17.   y(x)+     Ax – At + Bx – Ct + D y(t) dt = f(x).
                            a
                                                                                      2
                                                                2
                     This is a special case of equation 2.9.6 with g(x)= Ax + Bx + D and h(t)= –At – Ct.
                        Solution:
                                               x
                                                  ∂ 2  Y 1 (x)Y 2 (t) – Y 2 (x)Y 1 (t)
                                  y(x)= f(x)+                              f(t) dt.
                                                 ∂x∂t         W(t)
                                              a
                     Here Y 1 (x), Y 2 (x) is a fundamental system of solutions of the second-order homogeneous

                     ordinary differential equation Y      + (B – C)x + D Y +(2Ax + B)Y = 0 (see A. D. Polyanin

                                              xx               x
                     and V. F. Zaitsev (1996) for details about this equation):
                                           1  1       2                       1  1       2
                        Y 1 (x)=exp(–kx)Φ α,  ;  (C – B)z ,  Y 2 (x) = exp(–kx)Ψ α,  ;  (C – B)z ,
                                           2  2                               2  2
                                        √
                                          2π(C – B)             2             2A
                                W(x)= –            exp  1 (C – B)z – 2kx ,  k =   ,
                                           Γ(α)        2                     B – C
                                     2
                                   4A +2AD(C – B)+ B(C – B)  2         4A +(C – B)D
                              α = –                           ,  z = x –            ,
                                            2(C – B) 3                    (C – B) 2

                     where Φ α, β; x and Ψ α, β; x are degenerate hypergeometric functions and Γ(α)isthe
                     gamma function.
                             x


               18.   y(x) –    Ax + B +(Cx + D)(x – t) y(t) dt = f(x).
                            a
                     This is a special case of equation 2.9.11 with g(x)= Ax + B and h(x)= Cx + D.
                        Solution with A ≠ 0:
                                                 x
                                                                         f(t)



                                    y(x)= f(x)+    Y (x)Y 1 (t) – Y (x)Y 2 (t)  dt.
                                                    2          1
                                                a                       W(t)
                     Here Y 1 (x), Y 2 (x) is a fundamental system of solutions of the second-order homogeneous
                     ordinary differential equation Y xx  – (Ax + B)Y – (Cx + D)Y = 0 (see A. D. Polyanin and


                                                           x
                     V. F. Zaitsev (1996) for details about this equation):
                                                1  1  2                       1  1  2
                             Y 1 (x) = exp(–kx)Φ α,  ;  Az ,  Y 2 (x) = exp(–kx)Ψ α,  ;  Az ,
                                                2  2                          2  2
                                          √
                                                       –1     1  2
                                   W(x)= – 2πA Γ(α)    exp   Az – 2kx ,  k = C/A,
                                                           2
                                                                              –2
                                      1
                                                      2
                                          2
                                                         –3
                                   α = (A D – ABC – C )A ,   z = x +(AB +2C)A ,
                                      2

                     where Φ α, β; x and Ψ α, β; x are degenerate hypergeometric functions, Γ(α) is the gamma
                     function.
                               x

               19.   y(x)+     At + B +(Ct + D)(t – x) y(t) dt = f(x).
                            a
                     This is a special case of equation 2.9.12 with g(t)= –At – B and h(t)= –Ct – D.
                        Solution with A ≠ 0:
                                                  x                      f(t)

                                    y(x)= f(x) –   Y 1 (x)Y (t) – Y (t)Y 2 (x)  dt.


                                                        2
                                                               1
                                                a                       W(x)
                     Here Y 1 (x), Y 2 (x) is a fundamental system of solutions of the second-order homogeneous

                     ordinary differential equation Y      – (Ax + B)Y – (Cx + D)Y = 0 (see A. D. Polyanin and
                                              xx           x
                     V. F. Zaitsev (1996) for details about this equation):
                                                1  1  2                       1  1  2
                             Y 1 (x) = exp(–kx)Φ α,  ;  Az ,  Y 2 (x) = exp(–kx)Ψ α,  ;  Az ,
                                                2  2                          2  2
                                          √
                                                       –1    1  2
                                   W(x)= – 2πA Γ(α)    exp   Az – 2kx ,  k = C/A,
                                                           2
                                                                              –2
                                          2
                                                      2
                                      1
                                                         –3
                                   α = (A D – ABC – C )A ,   z = x +(AB +2C)A ,
                                      2

                     where Φ α, β; x and Ψ α, β; x are degenerate hypergeometric functions and Γ(α)isthe
                     gamma function.
                 © 1998 by CRC Press LLC
               © 1998 by CRC Press LLC
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