Metamath Proof Explorer


Theorem fnopafv2b

Description: Equivalence of function value and ordered pair membership, analogous to fnopfvb . (Contributed by AV, 6-Sep-2022)

Ref Expression
Assertion fnopafv2b FFnABAF''''B=CBCF

Proof

Step Hyp Ref Expression
1 fnbrafv2b FFnABAF''''B=CBFC
2 df-br BFCBCF
3 1 2 bitrdi FFnABAF''''B=CBCF