deletions | additions       diff --git a/untitled.tex b/untitled.tex  index eb6d4ed..54a6494 100644  --- a/untitled.tex  +++ b/untitled.tex 
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A^{-1}=\frac{1}{|A|}  \begin{bmatrix}  \begin{matrix} \end{matrix} \begin{vmatrix} a_{22} & a_{23} \\ a_{32} & a_{33}\end{vmatrix}  \end{bmatrix}  \end{equation}