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Chapter 2


               Linear Equations of the Second Kind

               With Variable Limit of Integration






                 Notation: f = f(x), g = g(x), h = h(x), K = K(x), and M = M(x) are arbitrary functions (these
               may be composite functions of the argument depending on two variables x and t); A, B, C, D, a,
               b, c, α, β, γ, λ, and µ are free parameters; and m and n are nonnegative integers.


               2.1. Equations Whose Kernels Contain Power-Law
                      Functions

                 2.1-1. Kernels Linear in the Arguments x and t

                                x
               1.    y(x)– λ   y(t) dt = f(x).
                             a
                     Solution:
                                                            x
                                            y(x)= f(x)+ λ   e λ(x–t) f(t) dt.
                                                          a
                                 x
               2.    y(x)+ λx    y(t) dt = f(x).
                              a
                     Solution:
                                                      x

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

               3.    y(x)+ λ    ty(t) dt = f(x).
                             a
                     Solution:
                                                      x

                                                             1  2   2
                                       y(x)= f(x)– λ   t exp  λ(t – x ) f(t) dt.
                                                            2
                                                     a
                                x
               4.    y(x)+ λ   (x – t)y(t) dt = f(x).
                             a
                     This is a special case of equation 2.1.34 with n =1.
                     1 . Solution with λ >0:
                      ◦
                                                    x                      √
                                    y(x)= f(x)– k   sin[k(x – t)]f(t) dt,  k =  λ.
                                                  a


                 © 1998 by CRC Press LLC









               © 1998 by CRC Press LLC
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