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x

                           β  λ    β  λ
               20.       t ln x – x ln t)y(t) dt = f(x).
                      a
                                                                λ
                                                                             β
                     This is a special case of equation 1.9.11 with g(x)=ln x and h(t)= t .
                         x
                           β  λ        µ  γ
               21.       At ln x + Bx ln t)y(t) dt = f(x).
                      a
                                                                   λ
                                                                              β
                                                                                         µ
                     This is a special case of equation 1.9.15 with g 1 (x)= A ln x, h 1 (t)= t , g 2 (x)= Bx , and
                            γ
                     h 2 (t)=ln t.
                             µ
                         x     x + b
               22.      ln    λ     y(t) dt = f(x).
                      a     ct + s
                                                                 µ
                                                                                    λ
                     This is a special case of equation 1.9.6 with g(x) = ln(x + b) and h(t)= – ln(ct + s).
               1.5. Equations Whose Kernels Contain Trigonometric
                      Functions

                 1.5-1. Kernels Containing Cosine


                         x
               1.       cos[λ(x – t)]y(t) dt = f(x).
                      a
                                              x

                     Solution: y(x)= f (x)+ λ 2  f(x) dx.

                                    x
                                             a
                         x

               2.        cos[λ(x – t)] – 1 y(t) dt = f(x),  f(a)= f (a)= f      (x)=0.

                                                                 x      xx
                      a
                                     1


                     Solution: y(x)= –  f xxx (x) – f (x).
                                                x
                                    λ 2
                         x

               3.        cos[λ(x – t)] + b y(t) dt = f(x).
                      a
                     For b = 0, see equation 1.5.1. For b = –1, see equation 1.5.2. For λ = 0, see equation 1.1.1.
                     Differentiating the equation with respect to x, we arrive at an equation of the form 2.5.16:
                                              λ     x                 f (x)

                                                                       x
                                       y(x) –        sin[λ(x – t)]y(t) dt =  .
                                             b +1  a                   b +1
                     1 . Solution with b(b + 1)>0:
                      ◦
                                f (x)     λ 2     x                                   b

                                 x

                          y(x)=      +            sin[k(x – t)]f (t) dt,  where  k = λ   .
                                                             t
                                b +1   k(b +1) 2  a                                 b +1
                      ◦
                     2 . Solution with b(b + 1)<0:
                               f (x)     λ 2     x                                    –b

                                x

                         y(x)=       +            sinh[k(x – t)]f (t) dt,  where  k = λ  .
                                                             t
                                b +1   k(b +1) 2                                     b +1
                                               a
                 © 1998 by CRC Press LLC






                © 1998 by CRC Press LLC
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