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under the initial conditions
                                               Y (a)=0,  Y (a)= f(a).                       (2)

                                                          x
                        A fundamental system of solutions of the homogeneous equation (1) with f ≡ 0 has the
                     form
                                     A      m  λx             A      m  λx

                           Y 1 (x)= Φ  ,1; –  e   ,  Y 2 (x)= Ψ  ,1; –  e  ,  m = A + B,
                                     m      λ                 m      λ

                     where Φ α, β; x and Ψ α, β; x are degenerate hypergeometric functions.
                        Solving the homogeneous equation (1) under conditions (2) for an arbitrary function

                     f = f(x) and taking into account the relation y(x)= Y (x), we thus obtain the solution of the
                                                               x
                     integral equation in the form
                                                          x

                                            y(x)= f(x) –   R(x, t)f(t) dt,
                                                         a
                                      Γ(A/m) ∂  2      
  m  λt
                              R(x, t)=              exp   e    Y 1 (x)Y 2 (t) – Y 2 (x)Y 1 (t)  .
                                         λ    ∂x∂t       λ
                              x

                                   λ(x+t)  2λt
               7.    y(x)+ A    e      – e   y(t) dt = f(x).
                              a
                                         λx
                     The transformation z = e , τ = e λt  leads to an equation of the form 2.1.4.
                     1 . Solution with Aλ >0:
                      ◦
                                                x
                                                 λt
                                                             λt


                               y(x)= f(x) – λk  e sin k(e λx  – e ) f(t) dt,  k =  A/λ.
                                              a
                     2 . Solution with Aλ <0:
                      ◦
                                               x
                                                λt
                                                              λt
                              y(x)= f(x)+ λk   e sinh k(e λx  – e ) f(t) dt,  k =    |A/λ|.


                                             a
                              x

                                   λx+µt  (λ+µ)t
               8.    y(x)+ A    e      – e     y(t) dt = f(x).
                              a
                                                µt
                                         µx
                     The transformation z = e , τ = e , Y (z)= y(x) leads to an equation of the form 2.1.52:
                                         A     z  k  k
                                  Y (z)+      (z – τ )Y (τ) dτ = F(z),  F(z)= f(x),
                                         µ  b
                                      µa
                     where k = λ/µ, b = e .
                              x

                                   λx+µt         (λ+µ)x
               9.    y(x)+ A    λe      – (λ + µ)e     y(t) dt = f(x).
                              a
                     This equation can be obtained by differentiating an equation of the form 1.2.22:
                                 x                                           x

                                         λx  µt  µx
                                   1+ Ae (e   – e ) y(t) dt = F(x),  F(x)=    f(t) dt.
                                a                                           a
                        Solution:
                                               x
                                  d     λx       F(t)       dt               Aµ  (λ+µ)x
                           y(x)=      e Φ(x)                ,    Φ(x)=exp       e      .
                                  dx          a   e λt  t  Φ(t)             λ + µ
                 © 1998 by CRC Press LLC









               © 1998 by CRC Press LLC
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