deletions | additions       diff --git a/Ex 1.tex b/Ex 1.tex  index dcc0430..509aa50 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} \\  \rule{4}  \iff & \left(x < 0 \to \wp{y:= -x}{R}\right) \a \left(0 \leq x \to \wp{y:= x}{R}\right)\\ \rule{1}  \iff & (x < 0 \to (0 \leq -x \a (0 \leq x \to -x = x) \a (x < 0 \to -x = -x )))\\ \land & (x \leq 0 \to (0 \leq x \a (0 \leq x \to x = x) \a (x < 0 \to x = -x)))\\  \iff & (x < 0 \to -x = -x) \a (0 \leq x \to x = x)\\  \iff & \T\\