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–1
                     where L  R(p) is the inverse Laplace transform of the function
                                                                  n
                                                K(p)                  A k
                                        R(p)=         ,    K(p)=          .                (11)
                                               1+ K(p)               p – λ k
                                                                  k=1
                        The transform R(p) of the resolvent R(x) can be represented as a regular fractional
                     function:
                                          Q(p)
                                   R(p)=      ,    P(p)=(p – µ 1 )(p – µ 2 ) ... (p – µ n ),
                                          P(p)
                     where Q(p) is a polynomial in p of degree < n. The roots µ k of the polynomial P(p) coincide
                     with the roots of equation (8). If all µ k are real and different, then the resolvent can be
                     determined by the formula

                                                 n
                                                      µ k x        Q(µ k )
                                         R(x)=     B k e  ,   B k =      ,
                                                                   P (µ k )

                                                k=1
                     where the prime stands for differentiation.

                 2.2-2. Kernels Containing Power-Law and Exponential Functions

                                x
               20.   y(x)+ A    xe λ(x–t) y(t) dt = f(x).
                              a
                     Solution:
                                                   x
                                                                2
                                                            2
                                  y(x)= f(x) – A   x exp    1  A(t – x )+ λ(x – t) f(t) dt.

                                                        2
                                                 a
                              x

               21.   y(x)+ A    te λ(x–t) y(t) dt = f(x).
                              a
                     Solution:
                                                  x

                                                          1  2  2
                                   y(x)= f(x) – A  t exp  A(t – x )+ λ(x – t) f(t) dt.
                                                        2
                                                 a
                              x

                                      λt
               22.   y(x)+ A    (x – t)e y(t) dt = f(x).
                              a
                                                                λt
                     This is a special case of equation 2.9.4 with g(t)= Ae .
                        Solution:
                                              A     x                     λt
                                  y(x)= f(x)+        u 1 (x)u 2 (t) – u 2 (x)u 1 (t) e f(t) dt,
                                              W   a
                     where u 1 (x), u 2 (x) is a fundamental system of solutions of the second-order linear homo-
                                                            λx
                     geneous ordinary differential equation u     + Ae u = 0; the functions u 1 (x) and u 2 (x) are
                                                     xx
                     expressed in terms of Bessel functions or modified Bessel functions, depending on sign A:
                                            √                       √
                             λ              2 A   λx/2              2 A  λx/2
                        W =   ,   u 1 (x)= J 0   e     ,  u 2 (x)= Y 0   e        for A >0,
                             π                λ                       λ
                                            √                        √
                              λ             2 |A|  λx/2              2 |A|  λx/2
                        W = – ,   u 1 (x)= I 0   e     ,  u 2 (x)= K 0    e       for A <0.
                              2               λ                       λ
                 © 1998 by CRC Press LLC









               © 1998 by CRC Press LLC
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