deletions | additions       diff --git a/Ex3.b.tex b/Ex3.b.tex  index 7df7350..e03f049 100644  --- a/Ex3.b.tex  +++ b/Ex3.b.tex 
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\begin{equation}  \begin{split}  S_1 &= S_{11}; S_{12}\\  S_{11} &=  \end{split}  \end{equation}