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 ) = ∅ ) |
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 ) = ∅ ) |