Page 372 - Handbook Of Integral Equations
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x


               8.    y(x)+ k   exp λ(x – t)+ βy(t) dt = A.
                             a
                     Solution in an implicit form:
                                                       dt
                                                 y
                                                               = x – a.
                                                  λt – ke βt  – λA
                                               A
                              x



               9.    y(x)+ k   exp λ(x – t)+ βy(t) dt = Ae λx  + B.
                             a
                     Solution in an implicit form:
                                        y
                                              dt                       λa

                                                      = x – a,   y 0 = Ae  + B.
                                         λt – ke βt  – λB
                                       y 0
                              x

               10.   y(x)+ k   sinh[λ(x – t)] exp[βy(t)] dt = Ae λx  + Be –λx  + C.
                             a
                                                                 βy
                     This is a special case of equation 5.8.14 with f(y)= ke .
                                x
               11.   y(x)+ k   sinh[λ(x – t)] exp[βy(t)] dt = A cosh(λx)+ B.
                             a
                                                                 βy
                     This is a special case of equation 5.8.15 with f(y)= ke .
                                x
               12.   y(x)+ k   sinh[λ(x – t)] exp[βy(t)] dt = A sinh(λx)+ B.
                             a
                                                                 βy
                     This is a special case of equation 5.8.16 with f(y)= ke .
                              x

               13.   y(x)+ k   sin[λ(x – t)] exp[βy(t)] dt = A sin(λx)+ B cos(λx)+ C.
                             a
                                                                 βy
                     This is a special case of equation 5.8.17 with f(y)= ke .
                 5.4-2. Equations Containing Arbitrary Functions
                             x

               14.   y(x)+    f(t) exp[λy(t)] dt = A.
                            a
                     Solution:
                                                  1       x         –Aλ
                                           y(x)= –  ln λ   f(t) dt + e  .
                                                  λ      a

                               x
               15.   y(x)+    g(t) exp[λy(t)] dt = f(x).
                            a
                      ◦
                     1 . By differentiation, this integral equation can be reduced to the first-order ordinary differ-
                     ential equation
                                                 y + g(x)e λy  = f (x)                      (1)


                                                              x
                                                  x
                     under the initial condition y(a)= f(a). The substitution w = e –λy  reduces (1) to the linear
                     equation



                                    w + λf (x)w – λg(x)=0,    w(a)=exp –λf(a) .
                                     x     x
                     2 . Solution:
                      ◦
                                                             x
                                                 1
                                     y(x)= f(x) –  ln 1+ λ   g(t)exp λf(t) dt .
                                                 λ         a
                 © 1998 by CRC Press LLC







               © 1998 by CRC Press LLC
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