Metamath Proof Explorer


Theorem opelresi

Description: Ordered pair membership in a restriction. Exercise 13 of TakeutiZaring p. 25. (Contributed by NM, 13-Nov-1995)

Ref Expression
Hypothesis opelresi.1
|- C e. _V
Assertion opelresi
|- ( <. B , C >. e. ( R |` A ) <-> ( B e. A /\ <. B , C >. e. R ) )

Proof

Step Hyp Ref Expression
1 opelresi.1
 |-  C e. _V
2 opelres
 |-  ( C e. _V -> ( <. B , C >. e. ( R |` A ) <-> ( B e. A /\ <. B , C >. e. R ) ) )
3 1 2 ax-mp
 |-  ( <. B , C >. e. ( R |` A ) <-> ( B e. A /\ <. B , C >. e. R ) )