Page 174 - Handbook Of Integral Equations
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x

                                          m
                                  k
               22.   y(x) – A   sin (λx) sin (µt)y(t) dt = f(x).
                             a
                                                                                  m
                                                                  k
                     This is a special case of equation 2.9.2 with g(x)= A sin (λx) and h(t) = sin (µt).
                              x

               23.   y(x)+ A    t sin[λ(x – t)]y(t) dt = f(x).
                              a
                     This is a special case of equation 2.9.36 with g(t)= At.
                        Solution:
                                               Aλ     x
                                   y(x)= f(x)+       t u 1 (x)u 2 (t) – u 2 (x)u 1 (t) f(t) dt,
                                               W
                                                   a
                     where u 1 (x), u 2 (x) is a fundamental system of solutions of the second-order linear ordinary
                     differential equation u     + λ(Ax + λ)u = 0, and W is the Wronskian.
                                      xx
                        Depending on the sign of Aλ, the functions u 1 (x) and u 2 (x) are expressed in terms of
                     Bessel functions or modified Bessel functions as follows:
                        if Aλ > 0, then
                                               √                          √
                               u 1 (x)= ξ 1/2 J 1/3 3 2  Aλ ξ 3/2  ,  u 2 (x)= ξ 1/2  Y 1/3 3 2  Aλ ξ 3/2  ,
                                              W =3/π,    ξ = x +(λ/A);
                        if Aλ < 0, then
                                             √                            √
                              u 1 (x)= ξ 1/2  I 1/3 3 2  –Aλ ξ 3/2  ,  u 2 (x)= ξ 1/2  K 1/3 3 2  –Aλ ξ 3/2  ,
                                                     3
                                               W = – ,  ξ = x +(λ/A).
                                                     2
                              x

               24.   y(x)+ A    x sin[λ(x – t)]y(t) dt = f(x).
                              a
                     This is a special case of equation 2.9.37 with g(x)= Ax and h(t)=1.
                        Solution:
                                              Aλ     x
                                   y(x)= f(x)+       x u 1 (x)u 2 (t) – u 2 (x)u 1 (t) f(t) dt,
                                               W   a
                     where u 1 (x), u 2 (x) is a fundamental system of solutions of the second-order linear ordinary
                     differential equation u     + λ(Ax + λ)u = 0, and W is the Wronskian.
                                      xx
                        The functions u 1 (x), u 2 (x), and W are specified in 2.5.23.
                              x

                                     m
                                 k
               25.   y(x)+ A    t sin (λx)y(t) dt = f(x).
                              a
                                                                   m
                                                                                  k
                     This is a special case of equation 2.9.2 with g(x)= –A sin (λx) and h(t)= t .
                              x

                                 k
                                     m
               26.   y(x)+ A    x sin (λt)y(t) dt = f(x).
                              a
                                                                 k
                                                                              m
                     This is a special case of equation 2.9.2 with g(x)= –Ax and h(t) = sin (λt).
                               x

               27.   y(x) –    A sin(kx)+ B – AB(x – t) sin(kx) y(t) dt = f(x).
                            a
                     This is a special case of equation 2.9.7 with λ = B and g(x)= A sin(kx).
                        Solution:
                                                          x

                                            y(x)= f(x)+    R(x, t)f(t) dt,
                                                         a
                                           G(x)   B 2     x  B(x–s)                 A
                      R(x, t)=[A sin(kx)+ B]    +        e     G(s) ds,  G(x)=exp –  cos(kx) .
                                           G(t)   G(t)  t                          k
                 © 1998 by CRC Press LLC








               © 1998 by CRC Press LLC
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