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b

               27.   y(x) – λ  [AK µ (αx)+ BK ν (βt)]y(t) dt = f(x).
                             a
                     This is a special case of equation 4.9.5 with g(x)= AK µ (αx) and h(t)= BK ν (βt).

                                b
               28.   y(x) – λ  [AK µ (x)K µ (t)+ BK ν (x)K ν (t)]y(t) dt = f(x).
                             a
                     This is a special case of equation 4.9.14 with g(x)= K µ (x) and h(t)= K ν (t).


                              b
               29.   y(x) – λ  [AK µ (x)K ν (t)+ BK ν (x)K µ (t)]y(t) dt = f(x).
                             a
                     This is a special case of equation 4.9.17 with g(x)= K µ (x) and h(t)= K ν (t).

               4.9. Equations Whose Kernels Contain Arbitrary

                      Functions

                 4.9-1. Equations With Degenerate Kernel: K(x, t)= g 1 (x)h 1 (t)+ ··· + g n (x)h n (t)

                                b
               1.    y(x) – λ  g(x)h(t)y(t) dt = f(x).
                             a
                                          b         –1
                     1 . Assume that λ ≠  g(t)h(t) dt  .
                      ◦
                                        a
                        Solution:
                                                                 b          –1  b


                         y(x)= f(x)+ λkg(x),   where  k =  1 – λ  g(t)h(t) dt    h(t)f(t) dt.
                                                                a              a
                                          b         –1
                     2 . Assume that λ =  g(t)h(t) dt  .
                      ◦
                                        a
                             b

                        For   h(t)f(t) dt = 0, the solution has the form
                            a
                                                  y = f(x)+ Cg(x),
                     where C is an arbitrary constant.
                              b
                        For   h(t)f(t) dt ≠ 0, there is no solution.
                            a
                        The limits of integration may take the values a = –∞ and/or b = ∞, provided that the
                     corresponding improper integral converges.


                              b
               2.    y(x) – λ  [g(x)+ g(t)]y(t) dt = f(x).
                             a
                     The characteristic values of the equation:
                                                 1                   1
                                       λ 1 =   √        ,  λ 2 =   √        ,
                                           g 1 +  (b – a)g 2   g 1 –  (b – a)g 2

                     where

                                                b               b
                                                                  2
                                          g 1 =  g(x) dx,  g 2 =  g (x) dx.
                                               a               a

                 © 1998 by CRC Press LLC









               © 1998 by CRC Press LLC
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