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x

               8.    y(x) – A   e µ(x–t)  ln(λt)y(t) dt = f(x).
                             a
                     Solution:
                                                    x
                                                                  (λx) Ax
                                    y(x)= f(x)+ A    e (µ–A)(x–t)  ln(λt)  f(t) dt.
                                                                   (λt) At
                                                   a
                              x

               9.    y(x)+ A    e µ(x–t) (ln x – ln t)y(t) dt = f(x).
                              a
                     Solution:                   x
                                             1      µ(x–t)




                                 y(x)= f(x)+       e     u (x)u (t) – u (x)u (t) f(t) dt,
                                                              2
                                                                         1
                                                                    2
                                                          1
                                             W   a
                     where the primes stand for the differentiation with respect to the argument specified in the
                     parentheses, and u 1 (x), u 2 (x) is a fundamental system of solutions of the second-order linear
                                                               –1
                     homogeneous ordinary differential equation u     +Ax u = 0, with u 1 (x) and u 2 (x) expressed
                                                         xx
                     in terms of Bessel functions or modified Bessel functions, depending on the sign of A:
                                        √      √               √      √
                             1
                         W =   ,  u 1 (x)=  xJ 1 2 Ax ,  u 2 (x)=  xY 1 2 Ax     for  A >0,
                             π
                                        √      √               √      √
                              1
                         W = – ,  u 1 (x)=  xI 1 2 –Ax ,  u 2 (x)=  xK 1 2 –Ax   for  A <0.
                              2
                              ∞

               10.   y(x)+ a    e λ(x–t)  ln(t – x)y(t) dt = f(x).
                             x
                     This is a special case of equation 2.9.62 with K(x)= ae λx  ln(–x).
                 2.7-3.  Kernels Containing Exponential and Trigonometric Functions
                                x
               11.   y(x) – A   e µt  cos(λx)y(t) dt = f(x).
                             a
                                                                                µt
                     This is a special case of equation 2.9.2 with g(x)= A cos(λx) and h(t)= e .
                                x
               12.   y(x) – A   e µx  cos(λt)y(t) dt = f(x).
                             a
                     This is a special case of equation 2.9.2 with g(x)= Ae µx  and h(t) = cos(λt).
                                x
               13.   y(x)+ A    e µ(x–t)  cos[λ(x – t)]y(t) dt = f(x).
                              a
                      ◦
                     1 . Solution with |A| >2|λ|:
                                                          x
                                            y(x)= f(x)+    R(x – t)f(t) dt,
                                                        a

                                                 A 2
                                          1                                    1  2  2
                            R(x)=exp (µ – A)x       sinh(kx) – A cosh(kx) ,  k =  A – λ .
                                          2                                    4
                                                 2k
                     2 . Solution with |A| <2|λ|:
                      ◦
                                                         x

                                            y(x)= f(x)+    R(x – t)f(t) dt,
                                                        a
                                                  A 2

                                           1                                   2  1  2
                             R(x)=exp (µ – A)x       sin(kx) – A cos(kx) ,  k =  λ – A .
                                           2      2k                              4
                                         1
                     3 . Solution with λ = ± A:
                      ◦
                                         2
                                         x
                                                                  1  2             1
                          y(x)= f(x)+    R(x – t)f(t) dt,  R(x)=  A x – A exp µ – A x .
                                                                 2                 2
                                       a
                 © 1998 by CRC Press LLC

               © 1998 by CRC Press LLC
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