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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.
                                                                                          2
                      ◦
                     4 . Solution with λ = λ 1,2 = λ ∗ and f 1 = f 2 = 0, where the characteristic value λ ∗ =
                                                                                       A(b – a)
                     (A ≠ 0) is double:
                                                 y(x)= f(x)+ Cy ∗ (x),
                     where C is an arbitrary constant and y ∗ (x) is an eigenfunction of the equation corresponding
                     to λ ∗ . Two cases are possible.
                        (a) If A(b – a) ≠ –2Bh 1 , then

                                                          A(b – a)+2Bh 1
                                       y ∗ (x)= A + Bxh(x) –            h(x).
                                                               2h 0
                                                                   2
                                                               2
                        (b) If A(b – a)= –2Bh 1 , then, in view of h 0 [A(b – a )+2Bh 2 ] = 0,wehave
                                  
                                                                          2
                                                                              2
                                   A + Bxh(x)             for h 0 ≠ 0 and A(b – a )= –2Bh 2 ,
                                                                          2
                                                                              2
                           y ∗ (x)=  h(x)                  for h 0 = 0 and A(b – a ) ≠ –2Bh 2 ,
                                                                         2   2
                                    C 1 [A + Bxh(x)] + C 2 h(x)  for h 0 = 0 and A(b – a )= –2Bh 2 ,
                     where C 1 and C 2 are arbitrary constants.

                              b
               11.   y(x) – λ  [A +(Bx + Ct)h(x)]y(t) dt = f(x).
                             a
                     The characteristic values of the equation:
                                                                    √
                                                A(b – a)+(B + C)h 1 ±  D
                                  λ 1,2 =                                       ,
                                        C{2h 1 [A(b – a)+ Bh 1 ] – h 0 [A(b – a )+2Bh 2 ]}
                                                                  2
                                                                      2
                                                                       2
                                                         2
                                                                    2
                                  D =[A(b – a)+(B – C)h 1 ] +2Ch 0 [A(b – a )+2Bh 2 ],
                     where
                                        b               b                 b
                                                                           2
                                 h 0 =  h(x) dx,  h 1 =  xh(x) dx,  h 2 =  x h(x) dx.
                                      a               a                 a
                      ◦
                     1 . Solution with λ ≠ λ 1,2 :

                                        y(x)= f(x)+ λ AE 1 +(BE 1 x + E 2 )h(x) ,
                     where the constants E 1 and E 2 are given by
                            –1
                      E 1 = ∆ [f 1 – λC(f 1 h 1 – f 2 h 0 )],



                                                               2
                                                                   2
                      E 2 = C∆ –1    f 2 – λf 2 A(b – a)+ Bh 1 – λf 1 2 1  A(b – a )+ Bh 2    ,

                                                 1   2   2         2
                      ∆ = C h 1 [A(b – a)+ Bh 1 ] – h 0 2  A(b – a )+ Bh 2  λ – [A(b – a)+(B + C)h 1 ]λ +1,
                             b               b
                      f 1 =  f(x) dx,  f 2 =  xf(x) dx.
                           a               a
                      ◦
                     2 . Solution with λ = λ 1 ≠ λ 2 and f 1 = f 2 =0:
                                                                  1 – λ 1 [A(b – a)+ Bh 1 ]
                         y(x)= f(x)+ Cy 1 (x),  y 1 (x)= A + Bxh(x)+                 h(x),

                                                                         λ 1 h 0
                     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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