Metamath Proof Explorer


Theorem copsex2ga

Description: Implicit substitution inference for ordered pairs. Compare copsex2g . (Contributed by NM, 26-Feb-2014) (Proof shortened by Mario Carneiro, 31-Aug-2015)

Ref Expression
Hypothesis copsex2ga.1 ⊢ A = x y → φ ↔ ψ
Assertion copsex2ga ⊢ A ∈ V × W → φ ↔ ∃ x ∃ y A = x y ∧ ψ

Proof

Step Hyp Ref Expression
1 copsex2ga.1 ⊢ A = x y → φ ↔ ψ
2 xpss ⊢ V × W ⊆ V × V
3 2 sseli ⊢ A ∈ V × W → A ∈ V × V
4 1 copsex2gb ⊢ ∃ x ∃ y A = x y ∧ ψ ↔ A ∈ V × V ∧ φ
5 4 baibr ⊢ A ∈ V × V → φ ↔ ∃ x ∃ y A = x y ∧ ψ
6 3 5 syl ⊢ A ∈ V × W → φ ↔ ∃ x ∃ y A = x y ∧ ψ