Theorem an13s

Swap two conjuncts in antecedent. (Contributed by NM, 31-May-2006.)

Hypothesis
an12s.1
\( \vdash \varphi \wedge (\psi \wedge \chi) \rightarrow \theta \)
Conclusion
\( \vdash \chi \wedge (\psi \wedge \varphi) \rightarrow \theta \)
Proof
an12s.1
exp32 _
com13 _
imp32 _