Page 264 - Handbook Of Integral Equations
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b
               40.      f(t)y(x + βt) dt = Ae λx .
                      a
                     Solution:
                                              A  λx           b
                                       y(x)=   e ,     B =    f(t) exp(λβt) dt.
                                             B              a


                         b
               41.      f(t)y(x + βt) dt = A sin λx + B cos λx.
                      a
                     Solution:
                                               y(x)= p sin λx + q cos λx,

                     where

                                              AI c + BI s      BI c – AI s
                                           p =         ,    q =         ,
                                                                 2
                                                 2
                                                I + I 2         I + I 2
                                                c   s            c   s
                                           b                      b
                                    I c =  f(t) cos(λβt) dt,  I s =  f(t) sin(λβt) dt.
                                         a                      a
                       1

               42.      y(ξ) dt = f(x),  ξ = g(x)t.
                      0
                     Assume that g(0) = 0, g(1) = 1, and g ≥ 0.

                                                  x
                                                                                  1
                     1 . The substitution z = g(x) leads to an equation of the form 3.1.41:  y(zt) dt = F(z),
                      ◦
                                                                               0
                     where the function F(z) is obtained from z = g(x) and F = f(x) by eliminating x.
                     2 . Solution y = y(z) in the parametric form:
                      ◦
                                               g(x)
                                         y(z)=      f (x)+ f(x),   z = g(x).

                                                     x
                                               g (x)

                                                x
                       1

                         λ
               43.      t y(ξ) dt = f(x),  ξ = g(x)t.
                      0

                     Assume that g(0) = 0, g(1) = 1, and g ≥ 0.
                                                  x
                                                                                1
                                                                                λ
                     1 . The substitution z = g(x) leads to an equation of the form 3.1.42:  t y(zt) dt = F(z),
                      ◦
                                                                              0
                     where the function F(z) is obtained from z = g(x) and F = f(x) by eliminating x.
                     2 . Solution y = y(z) in the parametric form:
                      ◦
                                             g(x)
                                      y(z)=      f (x)+(λ +1)f(x),   z = g(x).

                                                  x
                                            g (x)

                                             x
                       b

                                       β
               44.      f(t)y(ξ) dt = Ax ,   ξ = xϕ(t).
                      a
                     Solution:
                                               A  β            b        β
                                         y(x)=   x ,    B =    f(t) ϕ(t) dt.                (1)
                                               B
                                                             a
                 © 1998 by CRC Press LLC





               © 1998 by CRC Press LLC
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