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292   6. Applications of Determinants in Mathematical Physics

          which is equivalent to (b). This completes the proof of Lemma 6.20.
          Exercise. Prove that
                                     (n+1)                 (n+1)
             ∂    p − q − 1        A n+1,q ∂A pn     ∂   A p+1,1   ∂A
          	               
                                           p,q−1
           ω    −           A pq  = −        n  + A 1q           +    n    ,
             ∂ρ      ρ       n       A n   ∂z      n  ∂z   A n        ∂z
                                                                       (n+1)

                          ∂A pq   A       ∂    n              ∂   1  A p+1,1


                                   (n+1)
                         ω   n  =  n+1,q     −    A pq  − A 1q  −
                           ∂z      A n    ∂ρ   ρ    n    n   ∂ρ   ρ    A n
                                      ∂   q − 1   p,q−1   p +1

                                 −      −        A     −         A p+1,q
                                     ∂ρ     ρ     n         ρ     n
                                                2
                                             (ω = −1).
          Note that some cofactors are scaled but others are unscaled. Hence, prove
          that

                  ∂    n − 2  E n−1   E n ∂  A n−1    A n−1 ∂
                ω    −             =                −           E n  ,
                  ∂ρ     ρ     A n    A n ∂z  A n      A n ∂z   A n

                        ∂   E n−1               ∂    n  E n−1
                      ω            =(−1) n  E n   −
                        ∂z   A n           A n  ∂ρ   ρ   A n

                                       A n−1  ∂    1
                                     +           −    E n  .
                                              ∂ρ   ρ  A n
                                        A n
          6.10.3  The Intermediate Solutions
          The solutions given in this section are not physically significant and are
          called intermediate solutions. However, they are used as a starting point in
          Section 6.10.5 to obtain physically significant solutions.
          Theorem. Equations (6.10.1) and (6.10.2) are satisfied by the function


          pairs P n (φ n ,ψ n ) and P (φ ,ψ ), where

                              n  n  n
                  ρ n−2 A n−1  ρ n−2
          a. φ n =         =   11  ,
                    A n−2     A n−1
                  ωρ n−2 E n−1  (−1) ωρ n−2  (−1) n−1 ωρ n−2
                                   n
          b. ψ n =           =     n−1,1  =              A 1n ,
                     A n−2       E                 A n−2
                                   n−1
                  A 11

          c. φ =      ,
                  ρ
              n    n−2
                  (−1) ωA 1n    2
                      n

          d. ψ =              (ω = −1).
                     ρ
              n       n−2
          The first two formulas are equivalent to the pair P n+1 (φ n+1 ,ψ n+1 ), where
                    ρ n−1
          e. φ n+1 =    ,
                    A 11
                    (−1) n+1 ωρ n−1
          f. ψ n+1 =             .
                        E n1
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