deletions | additions       diff --git a/Ex 1.tex b/Ex 1.tex  index 8c3513c..2a40ccb 100644  --- a/Ex 1.tex  +++ b/Ex 1.tex 
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\begin{equation}  \begin{split}  & \wp{\ie{x < 0}{y := -x}{ y := x }}{R} \\  \iff & (x < 0 \to \wp{y:= -x}{R}) \land (0 \leq x \to \wp{y:= x}{R}) x}{R})\\  \iff & (x < 0 \to (0 \leq -x \land (0 \leq x \to -x = x) \land (x < 0 \to -x = -x )))  \end{split}  \end{equation}