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3 . In the special case a = 0 and A > 0, the solution of the integral equation is given by
                      ◦
                     formula (4) with

                                   I s (1 + cos λ) – I c (λ + sin λ)  I s sin λ + I c (1 + cos λ)
                             C 1 = k                     ,    C 2 = k                 ,
                                      2+2 cos λ + λ sin λ            2 + 2 cos λ + λ sin λ
                                                 b                       b
                             √
                          k =  2A, λ = bk, I s =  sin[k(b – t)]f(t) dt, I c =  cos[k(b – t)]f(t) dt.
                                               0                       0


                 4.1-2. Kernels Quadratic in the Arguments x and t

                              b

                                     2
                                 2
               7.    y(x) – λ  (x + t )y(t) dt = f(x).
                             a
                     The characteristic values of the equation:
                                          1                                1
                          λ 1 =                         ,  λ 2 =                         .
                               1  (b – a )+  1 (b – a )(b – a)  1  (b – a ) –  1  (b – a )(b – a)
                                 3
                                             5
                                                                              5
                                                                      3
                                                                                  5
                                     3
                                                                  3
                                                 5
                               3           5                    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                               1      1
                                 f 1 – λ  f                       f 2 – λ  f
                                                                                5
                         A 1 =         1 3 1 ∆ 3 – f 2 ∆ 1  ,  A 2 =     1 3 2 ∆ 3 – f 1 ∆ 5  ,


                                                                                 2
                                                2
                                                                     2
                                    2
                              λ 2 1 ∆ – ∆ 1 ∆ 5 – λ∆ 3 +1      λ 2 1  ∆ – ∆ 1 ∆ 5 – λ∆ 3 +1
                                 9  3  5        3                  9  3  5       3
                                          b               b
                                                                           n
                                                                               n
                                                           2
                                   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:

                                                                         5
                                                                        b – a 5
                                                                  2
                                     y(x)= f(x)+ Cy 1 (x),  y 1 (x)= x +      ,
                                                                       5(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:
                      ◦

                                                                         5
                                                                        b – a 5
                                                                  2
                                     y(x)= f(x)+ Cy 2 (x),  y 2 (x)= x –      .
                                                                       5(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.
                 © 1998 by CRC Press LLC








               © 1998 by CRC Press LLC
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