WeBWorK Standalone Renderer

Find the $LDU$ factorization of $A= \left[\begin{array}{cc} 1 &3\cr -3 &-12 \end{array}\right].$ That is, write $A=LDU$ where $L$ is a lower triangular matrix with ones on the diagonal, $D$ is a diagonal matrix, and $U$ is an upper triangular matrix with ones on the diagonal.

$A=$ $\left[\Rule{0pt}{2.4em}{0pt}\right.$ $\left]\Rule{0pt}{2.4em}{0pt}\right.$ $\left[\Rule{0pt}{2.4em}{0pt}\right.$ $\left]\Rule{0pt}{2.4em}{0pt}\right.$ $\left[\Rule{0pt}{2.4em}{0pt}\right.$ $\left]\Rule{0pt}{2.4em}{0pt}\right.$

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