Page 136 - Handbook Of Integral Equations
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4 .For f(x) = cos(βx)  m    a k exp(–µ k x), a solution of the equation has the form
                      ◦
                                        k=1
                                             m                      m

                                y(x) = cos(βx)  B k exp(–µ k x) + sin(βx)  C k exp(–µ k x),  (4)
                                             k=1                    k=1
                     where the constants B k and C k are found by the method of undetermined coefficients. The
                     solution can also be constructed using the formulas given in 2.9.60.


                      ◦
                     5 .For f(x) = sin(βx)  m    a k exp(–µ k x), a solution of the equation has the form
                                        k=1
                                             m                      m

                                y(x) = cos(βx)  B k exp(–µ k x) + sin(βx)  C k exp(–µ k x),  (5)
                                             k=1                    k=1

                     where the constants B k and C k are found by the method of undetermined coefficients. The
                     solution can also be constructed using the formulas given in 2.9.61.

                                                      ◦
                      ◦
                                                         ◦
                     6 . To obtain the general solution in item 2 –5 , the solution (1) of the homogeneous equation
                     must be added to each right-hand side of (2)–(5).
                              x

                                      n
               36.   y(x)+ A    (x – t)t y(t) dt = f(x),  n =1, 2, ...
                              a
                     This is a special case of equation 2.1.49 with λ = n.
                              x

                                  n
                                      n
               37.   y(x)+ A    (x – t )y(t) dt = f(x),  n =1, 2, ...
                              a
                     This is a special case of equation 2.1.52 with λ = n.
                               x
                                    n+1      n      n
               38.   y(x)+     ABx     – ABx t – Ax – B y(t) dt = f(x),    n =1, 2, ...
                            a
                                                                n
                     This is a special case of equation 2.9.7 with g(x)= Ax and λ = B.
                        Solution:
                                                         x

                                            y(x)= f(x)+    R(x – t)f(t) dt,
                                                        a
                                                                x
                               n
                     R(x, t)=(Ax +B)exp   A   x n+1  –t n+1    +B 2  exp  A   s n+1 –t n+1    +B(x–s) ds.
                                         n +1                 t     n +1
                             x

                                    n       n+1     n
               39.   y(x)+     ABxt – ABt      + At + B y(t) dt = f(x),    n =1, 2, ...
                            a
                                                               n
                     This is a special case of equation 2.9.8 with g(t)= At and λ = B.
                        Solution:
                                                          x
                                            y(x)= f(x)+    R(x – t)f(t) dt,
                                                        a
                                                               x

                                n
                     R(x, t)= –(At +B)exp  A   t n+1  –x n+1    +B 2  exp  A   s n+1 –x n+1    +B(t–s) ds.
                                         n +1                 t     n +1


                 © 1998 by CRC Press LLC









               © 1998 by CRC Press LLC
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