Metamath Proof Explorer


Theorem bj-opelopabid

Description: Membership in an ordered-pair class abstraction. One can remove the DV condition on x , y by using opabid in place of opabidw . (Contributed by BJ, 22-May-2024)

Ref Expression
Assertion bj-opelopabid x x y | φ y φ

Proof

Step Hyp Ref Expression
1 df-br x x y | φ y x y x y | φ
2 opabidw x y x y | φ φ
3 1 2 bitri x x y | φ y φ