Theorem simprd

Deduction eliminating a conjunct. (Contributed by NM, 14-May-1993.) A translation of natural deduction rule /\ ER ( /\ elimination right), see [natded]. (Proof shortened by Wolf Lammen, 3-Oct-2013.)

Hypothesis
simprd.1
\( \vdash \varphi \rightarrow \psi \wedge \chi \)
Conclusion
\( \vdash \varphi \rightarrow \chi \)
Proof
simprd.1
ancomd _
\( \vdash \varphi \rightarrow \chi \wedge \psi \)
simpld _