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2.1-5. Kernels Containing Rational Functions

                                x



               40.   y(x)+ x –3  t 2Ax +(1 – A)t y(t) dt = f(x).
                               a
                     This equation can be obtained by differentiating the equation
                                 x                                         x

                                      2          2                           3
                                   Ax t +(1 – A)xt y(t) dt = F(x),  F(x)=   t f(t) dt,
                                a                                         a
                     which has the form 1.1.17:
                        Solution:
                                     1 d     –A     x  A–1             1     x  3
                               y(x)=       x     t   ϕ (t) dt ,  ϕ(x)=      t f(t) dt.

                                                      t
                                     x dx      a                       x  a
                                x  y(t) dt
               41.   y(x) – λ          = f(x).
                             0   x + t
                     Dixon’s equation. This is a special case of equation 2.1.62 with a = b = 1 and µ =0.
                     1 . The solution of the homogeneous equation (f ≡ 0) is
                      ◦
                                            y(x)= Cx β    (β > –1, λ > 0).                  (1)
                     Here C is an arbitrary constant, and β = β(λ) is determined by the transcendental equation

                                                                    1
                                                                      β
                                                                     z dz
                                        λI(β) = 1,   where  I(β)=         .                 (2)
                                                                   0  1+ z
                      ◦
                     2 . For a polynomial right-hand side,
                                                         N
                                                               n
                                                   f(x)=    A n x
                                                         n=0
                     the solution bounded at zero is given by
                                       
                                         N
                                               A n
                                       
                                                     n
                                                    x         for λ < λ 0 ,
                                            1 – (λ/λ n )
                                       
                                       
                                       
                                         n=0
                                 y(x)=
                                        N
                                               A n    n     β
                                       
                                       
                                                    x + Cx    for λ > λ 0 and λ ≠ λ n ,
                                       
                                           1 – (λ/λ n )
                                         n=0
                                                                    n

                                           1                n          (–1) m
                                     λ n =    ,    I(n)=(–1)  ln 2 +         ,
                                          I(n)                          m
                                                                   m=1
                     where C is an arbitrary constant, and β =β(λ) is determined by the transcendental equation (2).
                        For special λ = λ n (n =1, 2, ... ), the solution differs in one term and has the form
                                n–1                 N
                                                                          ¯
                                       A m     m            A m     m     λ n  n       n
                          y(x)=               x +                  x – A n   x ln x + Cx ,
                                    1 – (λ n /λ m )     1 – (λ n /λ m )   λ n
                                m=0                m=n+1
                                       π 2  n   (–1) k    –1
                           ¯
                     where λ n =(–1) n+1  +          .
                                      12   k=1  k 2
                 © 1998 by CRC Press LLC


               © 1998 by CRC Press LLC
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