Metamath Proof Explorer


Theorem ovprc2

Description: The value of an operation when the second argument is a proper class. (Contributed by Mario Carneiro, 26-Apr-2015)

Ref Expression
Hypothesis ovprc1.1 Rel dom 𝐹
Assertion ovprc2 ( ¬ 𝐵 ∈ V → ( 𝐴 𝐹 𝐵 ) = ∅ )

Proof

Step Hyp Ref Expression
1 ovprc1.1 Rel dom 𝐹
2 simpr ( ( 𝐴 ∈ V ∧ 𝐵 ∈ V ) → 𝐵 ∈ V )
3 1 ovprc ( ¬ ( 𝐴 ∈ V ∧ 𝐵 ∈ V ) → ( 𝐴 𝐹 𝐵 ) = ∅ )
4 2 3 nsyl5 ( ¬ 𝐵 ∈ V → ( 𝐴 𝐹 𝐵 ) = ∅ )