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Matrix Algebra - Jordan Matrix

Let A=[2105244356]A=\left[\begin{array}{ccc}2&10&5\\-2&-4&-4\\3&5&6\end{array}\right].
Find matrix TTJT1=AT \ni TJT^{-1}=A.

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my answer

I have found λ1=λ2=1,λ3=2\lambda_1=\lambda_2=1,\lambda_3=2.
JA=[110010002]J_A=\left[\begin{array}{ccc}1&1&0\\0&1&0\\0&0&2\end{array}\right].
Matrix T consists of eigen vectors of A, hence
T=[525525112]T=\left[\begin{array}{ccc}5&2&-5\\5&2&-5\\1&1&-2\end{array}\right]
but it means |T|=0 implies T has no invers. So..... ???? Please help..
Reply 1
My guess is the matrix is not diagonalisable and you don't actually have enough eigenvectors to form T. You need to use generalised eigenvectors here.

If you have the Jordan normal form J=(110010002)J = \begin{pmatrix} 1 & 1 & 0 \\ 0 & 1 & 0 \\ 0 & 0 & 2 \end{pmatrix}, then the change of basis matrix you need is T=(uvw)T = \begin{pmatrix} \mathbf{u} & \mathbf{v} & \mathbf{w} \end{pmatrix}, where Au=uA \mathbf{u} = \mathbf{u}, Av=v+uA \mathbf{v} = \mathbf{v} + \mathbf{u} and Aw=2wA \mathbf{w} = 2 \mathbf{w}.

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