Metamath Proof Explorer


Theorem xpv

Description: Cartesian product of a class and the universe. (Contributed by Peter Mazsa, 6-Oct-2020)

Ref Expression
Assertion xpv ⊢ A × V = x y | x ∈ A

Proof

Step Hyp Ref Expression
1 df-xp ⊢ A × V = x y | x ∈ A ∧ y ∈ V
2 vex ⊢ y ∈ V
3 iba ⊢ y ∈ V → x ∈ A ↔ x ∈ A ∧ y ∈ V
4 2 3 ax-mp ⊢ x ∈ A ↔ x ∈ A ∧ y ∈ V
5 4 opabbii ⊢ x y | x ∈ A = x y | x ∈ A ∧ y ∈ V
6 1 5 eqtr4i ⊢ A × V = x y | x ∈ A