Page 383 - A Course in Linear Algebra with Applications
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9.4:  Jordan  Normal  Form               367

       We   solve  this  system,  beginning  with  the  last  equation,  and
                       2x
       obtain  u 3  =  c 2e .  Next  u' 2 =  2u 2,  so that  u 2  =  c\e 2x  . Finally
       we  solve
                                               2x
                              u[  -  2ui  =  cie ,

       a  first  order  linear  equation,  and  find  the  solution  to  be

                                               2x
                              u\  — (CQ +  c 1x)e .

            Therefore

                                       ci    I  <?\


        and  since  Y  =  SU,  we  obtain


                                 Co  +  C\  +CiX
                                                    2x
                          Y  =  |  -CQ-CXX      \   e ,
                                       c 2

        from  which  the  values  of  the  functions  yi,y2,V3  can  be  read
        off.


        Exercises   9.4

        1.  Find  the  minimum  polynomials  of  the  following  matrices
        by inspection  :

            w(SS>w(Si)                 i ( c , (!S

                 / 3  0   0'
             (d)   0  2   1
                 \ 0  0   2
        2.  Let  A  be  an  n  x  n  matrix  and  S  an  invertible  n  x  n  ma-
        trix  over  a  field  F.  If  /  is  any  polynomial  over  F,  show  that
                        1
            1
        f(S~ AS)   =  S~ f(A)S.   Use this  result  to  give another  proof
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