Linear Algebra Unique Factorization

sportsfan1292
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Homework Statement


Assume that the matrix A is diagonalizable : A=PDP-1, where D is the diagonal matrix of eigenvalues. Show that this factorization is not always unique


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The Attempt at a Solution


I have a couple of theories. The first being that since the matrix D can be reordered in any way as long as the eigenvalues are on the diagonal.
The second is that A=P-1CP when C is the non diagonalized matrix.
 
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I like your first theory. The order of the eigenvalues on the main diagonal of D depends on the order of placement of eigenvectors in P.
 
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