deletions | additions       diff --git a/untitled.tex b/untitled.tex  index c51565f..38fc91a 100644  --- a/untitled.tex  +++ b/untitled.tex 
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Rules:  \begin{equation}  +-=\tilde +-=#  \\ \tilde+=- #+=-  \\ \tilde-=+ #-=+  \\ \\  ++=+ \\  --=- \\  \tilde\tilde=\tilde ##=#  \end{equation}