Page 210 - Handbook Of Integral Equations
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For equations 2.9.53–2.9.62, only particular solutions are given. To obtain the general solu-
               tion, one must add the general solution of the corresponding homogeneous equation 2.9.52 to the
               particular solution.

                             ∞

                                                  n
               53.   y(x)+     K(x – t)y(t) dt = Ax ,   n =0, 1, 2, ...
                            x
                     This is a special case of equation 2.9.55 with λ =0.
                     1 . A solution with n =0:
                      ◦
                                                A               ∞
                                          y(x)=   ,   B =1 +     K(–z) dz.
                                                B             0
                      ◦
                     2 . A solution with n =1:
                                   A    AC                ∞                 ∞
                             y(x)=   x –   ,    B =1 +     K(–z) dz,  C =    zK(–z) dz.
                                   B    B 2
                                                        0                 0
                     3 . A solution with n =2:
                      ◦
                                                A  2   AC      AC 2   AD
                                         y 2 (x)=  x – 2   x +2     –    ,
                                                B       B 2     B 3   B 2
                                     ∞                 ∞                   ∞

                                                                              2
                            B =1 +     K(–z) dz,  C =    zK(–z) dz,  D =     z K(–z) dz.
                                    0                 0                   0
                      ◦
                     4 . A solution with n =3, 4, ... is given by:
                                                                        ∞
                                         ∂  n    e λx 
                         λz
                               y n (x)= A              ,    B(λ)=1 +     K(–z)e   dz.
                                         ∂λ n  B(λ)
                                                     λ=0              0
                             ∞

               54.   y(x)+     K(x – t)y(t) dt = Ae λx .
                            x
                     A solution:
                                    A  λx               ∞      λz
                              y(x)=   e ,     B =1 +     K(–z)e  dz =1 + L{K(–z), –λ}.
                                    B                 0
                     The integral term in the expression for B is the Laplace transform of K(–z) with parameter –λ,
                     which may be calculated using tables of Laplace transforms (e.g., see H. Bateman and
                     A. Erd´ elyi (vol. 1, 1954) and V. A. Ditkin and A. P. Prudnikov (1965)).
                             ∞

                                                  n λx
               55.   y(x)+     K(x – t)y(t) dt = Ax e  ,   n =1, 2, ...
                            x
                     1 . A solution with n =1:
                      ◦
                                                     A   λx   AC  λx
                                               y 1 (x)=  xe  –   e ,
                                                     B        B 2
                                            ∞                    ∞

                                    B =1 +    K(–z)e λz  dz,  C =  zK(–z)e λz  dz.
                                            0                    0
                     It is convenient to calculate B and C using tables of Laplace transforms (with parameter –λ).
                     2 . A solution with n =2:
                      ◦
                                          A  2 λx   AC    λx     AC 2  AD     λx
                                    y 2 (x)=  x e  – 2  xe  + 2      –      e ,
                                          B          B 2         B 3   B 2
                                 ∞                    ∞                     ∞

                                                                               2
                        B =1 +     K(–z)e λz  dz,  C =  zK(–z)e λz  dz,  D =  z K(–z)e λz  dz.
                                0                    0                     0
                     3 . A solution with n =3, 4, ... is given by
                      ◦
                                   ∂            ∂ n     e λx               ∞      λz
                            y n (x)=  y n–1 (x)= A        ,    B(λ)=1 +     K(–z)e   dz.
                                   ∂λ           ∂λ n  B(λ)               0
                 © 1998 by CRC Press LLC









               © 1998 by CRC Press LLC
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