Metamath Proof Explorer


Theorem fnopfvb

Description: Equivalence of function value and ordered pair membership. (Contributed by NM, 7-Nov-1995)

Ref Expression
Assertion fnopfvb F Fn A B A F B = C B C F

Proof

Step Hyp Ref Expression
1 fnbrfvb F Fn A B A F B = C B F C
2 df-br B F C B C F
3 1 2 syl6bb F Fn A B A F B = C B C F