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∞

               40.       t z–1 y(t) dt = f(z).
                      0
                     The left-hand side of this equation is the Mellin transform of y(t)(z is treated as a complex
                     variable).
                        Solution:
                                               1     c+i∞  –z        2
                                        y(t)=          t f(z) dz,    i = –1.
                                              2πi
                                                   c–i∞
                        For specific f(z), one can use tables of Mellin and Laplace integral transforms to calculate
                     the integral.
                     •
                       References: H. Bateman and A. Erd´ elyi (vol. 2, 1954), V. A. Ditkin and A. P. Prudnikov (1965).

                 3.1-6. Equation Containing the Unknown Function of a Complicated Argument

                       1

               41.      y(xt) dt = f(x).
                      0
                     Solution:

                                                 y(x)= xf (x)+ f(x).
                                                         x

                     The function f(x) is assumed to satisfy the condition xf(x)  =0.
                                                                      x=0
                         1
                         λ
               42.      t y(xt) dt = f(x).
                      0
                                                         x

                                                            λ
                     The substitution ξ = xt leads to equation  ξ y(ξ) dξ = x λ+1 f(x). Differentiating with
                                                        0
                     respect to x yields the solution
                                              y(x)= xf (x)+(λ +1)f(x).

                                                      x
                                                                  λ+1
                     The function f(x) is assumed to satisfy the condition x  f(x)  =0.
                                                                        x=0
                       1

                           k     m
               43.      Ax + Bt )y(xt) dt = f(x).
                      0
                     The substitution ξ = xt leads to an equation of the form 1.1.50:
                                           x

                                                k+m    m           m+1
                                             Ax    + Bξ   y(ξ) dξ = x  f(x).
                                          0
                       1
                         y(xt) dt
               44.       √      = f(x).
                      0    1 – t
                     The substitution ξ = xt leads to Abel’s equation 1.1.36:
                                                  x
                                                    y(ξ) dξ  √

                                                    √     =  xf(x).
                                                     x – ξ
                                                 0
                        y(xt) dt
                         1
               45.            λ  = f(x),   0 < λ <1.
                      0  (1 – t)
                     The substitution ξ = xt leads to the generalized Abel equation 1.1.46:
                                                 x
                                                   y(ξ) dξ   1–λ

                                                          = x  f(x).
                                                   (x – ξ) λ
                                                0
                 © 1998 by CRC Press LLC







               © 1998 by CRC Press LLC
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