Page 301 - Determinants and Their Applications in Mathematical Physics
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286   6. Applications of Determinants in Mathematical Physics

          Hence, the first term of F is given by
                              ∗
                          A x A =(−1) n+1 Q n+1,n+2 Q n+2,n+1 .     (6.9.28)
                              x
          Differentiating (6.9.26) and referring to (6.9.6),

                              A xx = ω    ∂A rr
                                           ∂x
                                        c r
                                      r

                                  = ω         ∂A ss ∂θ s
                                               ∂θ s ∂x
                                        c r
                                      r     s

                                  = −       c r c s A rs,rs
                                       r  s

                                  =       † c r c s A rs ,          (6.9.29)
                                     r  s

                               A t =   ∂A ∂θ r
                                       ∂θ r ∂t
                                     r
                                           2
                                  = −ω    c A rr .                  (6.9.30)
                                           r
                                        r
          Hence, applying (6.9.13) and (6.9.19),
                                                        2
                        A xx + ωA t =     † c r c s A rs +
                                                       c A rr
                                                        r
                                     r  s            r

                                  =       c r c s A rs
                                     r  s
                                  = P n+2,n+2
                                  = Q n+2,n+2 + Q.                  (6.9.31)
          Hence, the second term of F is given by
                ∗
              A (A xx + ωA t )=(−1) (B − Q n+1,n+1 )(Q n+2,n+2 + Q).  (6.9.32)
                                  n
          Taking the complex conjugate of (6.9.31) and applying (6.9.20) and
          (6.9.15),
                                        ∗
                                   ∗
                        (A xx + ωA t ) = P n+2,n+2
                                    =(−1)  n+1 (Q n+2,n+2 − Q).     (6.9.33)
          Hence, the third term of F is given by
                         ∗
             A(A xx + ωA t ) =(−1) n+1 (B + Q n+1,n+1 )(Q n+2,n+2 − Q).  (6.9.34)
          Referring to (6.9.14),
                     1 (−1) A (A xx + ωA t )+ A(A xx + ωA t ) ∗

                             ∗
                          n
                     2
                         = BQ − Q n+1,n+1 Q n+2,n+2
                         = QQ n+1,n+2;n+1,n+2 − Q n+1,n+1 Q n+2,n+2 .
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