Page 272 - Handbook Of Integral Equations
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b
                                 2
                                    2
               8.    y(x) – λ  (x – t )y(t) dt = f(x).
                             a
                     The characteristic values of the equation:
                                                            1
                                                                          .
                                         λ 1,2 = ±
                                                             1
                                                  1  (b – a ) – (b – a )(b – a)
                                                                   5
                                                        3 2
                                                               5
                                                     3
                                                  9          5
                      ◦
                     1 . Solution with λ ≠ λ 1,2 :
                                                               2
                                              y(x)= f(x)+ λ(A 1 x + A 2 ),
                     where the constants A 1 and A 2 are given by

                                   f 1 + λ  1  f              –f 2 + λ  1  f  1
                                                                             5
                              A 1 =       3 1 ∆ 3 – f 2 ∆ 1  ,  A 2 =     3 2 ∆ 3 – f 1 ∆ 5  ,


                                               1
                                                                           1
                                   λ 2  1 ∆ 1 ∆ 5 – ∆ 2  +1    λ 2  1 ∆ 1 ∆ 5 – ∆ 2  +1
                                       5       9  2                5       9  2

                                         b               b
                                                           2
                                                                           n
                                                                               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:
                      ◦
                                                                          3
                                                                              3
                                                                    3 – λ 1 (b – a )
                                                                 2
                                   y(x)= f(x)+ Cy 1 (x),  y 1 (x)= x +          ,
                                                                     3λ 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.
                      ◦
                                b
                                   2
                                        2
               9.    y(x) – λ  (Ax + Bt )y(t) dt = f(x).
                             a
                     The characteristic values of the equation:

                                  1             1       2  2  4
                                                          3
                                  3  (A + B)∆ 3 ±  9  (A – B) ∆ + AB∆ 1 ∆ 5      n   n
                                                             5
                            λ 1,2 =               1   1                ,    ∆ n = b – a .
                                                   2
                                           2AB   ∆ – ∆ 1 ∆ 5
                                                9  3  5
                     1 . Solution with λ ≠ λ 1,2 :
                      ◦
                                                               2
                                              y(x)= f(x)+ λ(A 1 x + A 2 ),
                     where the constants A 1 and A 2 are given by
                                                             1
                                                            f
                                                Af 1 – ABλ  3 1 ∆ 3 – f 2 ∆ 1
                                     A 1 =        1  2  1      1              ,
                                          ABλ 2  ∆ – ∆ 1 ∆ 5 – (A + B)λ∆ 3 +1
                                                9  3  5        3
                                                            1     1
                                               Bf 2 – ABλ  3 2 ∆ 3 – f 1 ∆ 5
                                                           f
                                                                  5
                                     A 2 =        1  2  1      1              ,
                                          ABλ 2  ∆ – ∆ 1 ∆ 5 – (A + B)λ∆ 3 +1
                                                9  3  5        3
                                                b               b
                                                                  2
                                         f 1 =  f(x) dx,  f 2 =  x f(x) dx.
                                              a               a
                      ◦
                     2 . Solution with λ = λ 1 ≠ λ 2 and f 1 = f 2 =0:
                                                                              3
                                                                           3
                                                                   3 – λ 1 A(b – a )
                                                                2
                                  y(x)= f(x)+ Cy 1 (x),  y 1 (x)= x +           ,
                                                                     3λ 1 A(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 .
                 © 1998 by CRC Press LLC
               © 1998 by CRC Press LLC
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