Page 190 - A Course in Linear Algebra with Applications
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174              Chapter  Six:  Linear  Transformationns


             matrix  A  with  respect  to  B  and  C,  and  by  a  matrix  A'  with
             respect  to  B'  and  C,  then

                                     A'  =    YAX-\




                 The   most  important   case  is  that  of  a  linear  operator
             T  : V  —•  V,  when the  ordered  basis  B  is used  for both  domain
             and  codomain.

             Theorem     6.2.6
             Let  B  and  B'  be two  ordered bases of  a  finite-dimensional vec-
             tor  space V  and  let T  be a linear  operator  on  V.  If  T  is  repre-
             sented  by matrices  A  and  A'  with  respect  to  B  and  B'  respec-
             tively,  then
                                      A'  =   SAS' 1

             where S  is  the  matrix  representing  the  change  of basis B  —>  B'.
             Example    6.2.11
             Let  T  be the  linear  transformation  on  -Ps(R)  defined  by
                     /
             T(/)  = '.  Consider  the  ordered  bases  of  Pa(R)
                                 2
                       B  =  {l,x,x }  and  B'  =  {l,2x,4x 2  -  2}.

                 We saw in Example    6.2.9 that  the  change  of basis  B  —>  B'
             is represented  by  the  matrix

                                      / l    0    1/2'
                                 17 =   0   1/2    0
                                      \ 0    0    1/4

             Now  T  is represented  with  respect  to  B  by the  matrix



                                   A
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