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Question 2.7.22: Find the PA = LU factorizations (and check them) for A= [ 0 ...

Find the PA = LU factorizations (and check them) for
A=\left[ \begin{matrix} 0 & 1 & 1 \\ 1 & 0 & 1 \\ 2 & 3 & 4 \end{matrix} \right] and A=\left[ \begin{matrix} 1 & 2 & 0 \\ 2 & 4 & 1 \\ 1 & 1 & 1 \end{matrix} \right].

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\left[ \begin{matrix} & 1 & \\ 1 & & \\ & & 1 \end{matrix} \right]A=\left[ \begin{matrix} 1 & & \\ 0 & 1 & \\ 2 & 3 & 1 \end{matrix} \right] \left[ \begin{matrix} 1 & 0 & 1 \\ & 1 & 1 \\ & & -1 \end{matrix} \right] ;

\left[ \begin{matrix} 1 & & \\ & & 1 \\ & 1 & \end{matrix} \right] A=\left[ \begin{matrix} 1 & & \\ 1 & 1 & \\ 2 & 0 & 1 \end{matrix} \right] \left[ \begin{matrix} 1 & 2 & 0 \\ & -1 & 1 \\ & & 1\end{matrix} \right]

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