Metamath Proof Explorer


Theorem funopafvb

Description: Equivalence of function value and ordered pair membership, analogous to funopfvb . (Contributed by Alexander van der Vekens, 25-May-2017)

Ref Expression
Assertion funopafvb
|- ( ( Fun F /\ A e. dom F ) -> ( ( F ''' A ) = B <-> <. A , B >. e. F ) )

Proof

Step Hyp Ref Expression
1 funfn
 |-  ( Fun F <-> F Fn dom F )
2 fnopafvb
 |-  ( ( F Fn dom F /\ A e. dom F ) -> ( ( F ''' A ) = B <-> <. A , B >. e. F ) )
3 1 2 sylanb
 |-  ( ( Fun F /\ A e. dom F ) -> ( ( F ''' A ) = B <-> <. A , B >. e. F ) )