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3 . Solution with n =2:
                      ◦
                                                A  2   AC      AC 2   AD
                                         y 2 (x)=  x – 2   x +2     –    ,
                                                B       B 2     B 3   B 2
                                    ∞                 ∞                  ∞

                                                                            2
                              B =     K(–z) dz,  C =    zK(–z) dz,  D =    z K(–z) dz.
                                   0                 0                  0
                      ◦
                     4 . Solution with n =3, 4, ... is given by
                                            n     λx                   ∞
                                           ∂    e                             λz
                                y n (x)= A               ,    B(λ)=     K(–z)e  dz.
                                          ∂λ n  B(λ)
                                                      λ=0            0
                       ∞

               28.       K(x – t)y(t) dt = Ae λx .
                      x
                     Solution:
                                              A  λx            ∞      λz
                                        y(x)=   e ,     B =     K(–z)e  dz.
                                              B              0
                     The expression for B is the Laplace transform of the function K(–z) with parameter p=–λ and
                     can be calculated with the aid of tables of Laplace transforms given (e.g., see Supplement 4).

                       ∞

                                            n λx
               29.       K(x – t)y(t) dt = Ax e  ,   n =1, 2, ...
                      x
                     1 . Solution with n =1:
                      ◦
                                                     A   λx   AC  λx
                                               y 1 (x)=  xe  –   e ,
                                                     B        B 2

                                           ∞                    ∞
                                     B =     K(–z)e λz  dz,  C =  zK(–z)e λz  dz.
                                          0                    0
                     It is convenient to calculate the coefficients B and C using tables of Laplace transforms with
                     parameter p = –λ.
                     2 . Solution with n =2:
                      ◦
                                                                    2
                                          A  2 λx   AC    λx     AC    AD    λx
                                    y 2 (x)=  x e  – 2  xe  + 2      –      e ,
                                          B          B 2         B  3  B 2
                               ∞                    ∞                      ∞

                                                                              2
                          B =     K(–z)e λz  dz,  C =  zK(–z)e λz  dz,  D =  z K(–z)e λz  dz.
                               0                    0                     0
                      ◦
                     3 . Solution with n =3, 4, ... is given by:
                                     ∂            ∂ n     e λx            ∞      λz
                             y n (x)=  y n–1 (x)= A         ,    B(λ)=     K(–z)e  dz.
                                    ∂λ           ∂λ n  B(λ)             0
                       ∞

               30.       K(x – t)y(t) dt = A cosh(λx).
                      x
                     Solution:
                               A   λx   A   –λx  1  	  A  A  
         1  	  A  A
                        y(x)=     e   +    e   =       +     cosh(λx)+       –     sinh(λx),
                              2B +     2B –      2 B +   B –           2 B +   B –
                                           ∞                     ∞

                                     B + =   K(–z)e λz  dz,  B – =  K(–z)e –λz  dz.
                                          0                     0



                 © 1998 by CRC Press LLC









                © 1998 by CRC Press LLC
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