Page 275 - Handbook Of Integral Equations
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where the constants A 1 and A 2 are given by

                                        1                                1      1
                                 f 1 – λ  4 1 ∆ 4 – f 2 ∆ 1       f 2 – λ  4 2 ∆ 4 – f 1 ∆ 7
                                                                          f
                                         f
                        A 1 =      1   1        1       , A 2 =     1    1        7  1    ,
                                    2
                                                                      2
                             λ 2   ∆ – ∆ 1 ∆ 7 – λ∆ 4 +1       λ 2  ∆ – ∆ 1 ∆ 7 – λ∆ 4 +1
                                 16  4  7       2                  16  4  7       2
                                          b               b
                                                                           n
                                                           3
                                                                               n
                                   f 1 =  f(x) dx,  f 2 =  x f(x) dx,  ∆ n = b – a .
                                        a               a
                      ◦
                     2 . Solution with λ = λ 1 ≠ λ 2 and f 1 = f 2 =0:

                                                                         7
                                                                        b – a 7
                                                                  3
                                     y(x)= f(x)+ Cy 1 (x),  y 1 (x)= x +      ,
                                                                       7(b – a)
                     where C is an arbitrary constant and y 1 (x) is an eigenfunction of the equation corresponding
                     to the characteristic value λ 1 .
                     3 . Solution with λ = λ 2 ≠ λ 1 and f 1 = f 2 =0:
                      ◦

                                                                         7
                                                                        b – a 7
                                                                  3
                                     y(x)= f(x)+ Cy 2 (x),  y 2 (x)= x –      ,
                                                                       7(b – a)
                     where C is an arbitrary constant and y 2 (x) is an eigenfunction of the equation corresponding
                     to the characteristic value λ 2 .
                      ◦
                     4 . The equation has no multiple characteristic values.
                                b
                                    3
                                 3
               21.   y(x) – λ  (x – t )y(t) dt = f(x).
                             a
                     The characteristic values of the equation:
                                                            1
                                                                          .
                                         λ 1,2 = ±
                                                             1
                                                  1  (a – b ) – (a – b )(b – a)
                                                     4
                                                                   7
                                                               7
                                                        4 2
                                                  4          7
                     1 . Solution with λ ≠ λ 1,2 :
                      ◦
                                                               3
                                              y(x)= f(x)+ λ(A 1 x + A 2 ),
                     where the constants A 1 and A 2 are given by
                                            1                           1     1
                                           f
                                   f 1 + λ  4 1 ∆ 4 – f 2 ∆ 1  –f 2 + λ  4 2 ∆ 4 – f 1 ∆ 7
                                                                       f
                              A 1 =     1      1       ,  A 2 =      1      1  7     ,
                                   λ 2  ∆ 1 ∆ 7 –  ∆ 2  +1     λ 2  ∆ 1 ∆ 7 –  ∆ 2  +1
                                       7       16  4               7       16  4
                                          b               b
                                                                               n
                                                           3
                                                                           n
                                   f 1 =  f(x) dx,  f 2 =  x f(x) dx,  ∆ n = b – a .
                                        a               a
                     2 . Solution with λ = λ 1 ≠ λ 2 and f 1 = f 2 =0:
                      ◦
                                                                              4
                                                                          4
                                                                    4 – λ 1 (b – a )
                                                                 3
                                   y(x)= f(x)+ Cy 1 (x),  y 1 (x)= x +          ,
                                                                     4λ 1 (b – a)
                     where C is an arbitrary constant and y 1 (x) is an eigenfunction of the equation corresponding
                     to the characteristic value λ 1 .
                                                                                           ◦
                      ◦
                     3 . The solution with λ = λ 2 ≠ λ 1 and f 1 = f 2 = 0 is given by the formulas of item 2 in
                     which one must replace λ 1 and y 1 (x)by λ 2 and y 2 (x), respectively.
                      ◦
                     4 . The equation has no multiple characteristic values.
                 © 1998 by CRC Press LLC
               © 1998 by CRC Press LLC
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