Metamath Proof Explorer


Theorem oprcl

Description: If an ordered pair has an element, then its arguments are sets. (Contributed by Mario Carneiro, 26-Apr-2015)

Ref Expression
Assertion oprcl ⊢ C ∈ A B → A ∈ V ∧ B ∈ V

Proof

Step Hyp Ref Expression
1 n0i ⊢ C ∈ A B → ¬ A B = ∅
2 opprc ⊢ ¬ A ∈ V ∧ B ∈ V → A B = ∅
3 1 2 nsyl2 ⊢ C ∈ A B → A ∈ V ∧ B ∈ V