deletions | additions       diff --git a/Polters.tex b/Polters.tex  index 83107a9..ec38f21 100644  --- a/Polters.tex  +++ b/Polters.tex 
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\times  \begin{bmatrix}b_1 & b_4 \\b_2 & b_3\end{bmatrix}  =  \begin{bmatrix}a_1b_4 \begin{bmatrix}a_2b_4  - a_4b_1 a_4b_2  & a_1b_3-a_3b_1\\a_3b_1-a_1b_3 & a_4b_2 - a_2b_4\end{bmatrix} \end{equation}