Metamath Proof Explorer


Theorem aovrcl

Description: Reverse closure for an operation value, analogous to afvvv . In contrast to ovrcl , elementhood of the operation's value in a set is required, not containing an element. (Contributed by Alexander van der Vekens, 26-May-2017)

Ref Expression
Hypothesis aovprc.1 Rel dom 𝐹
Assertion aovrcl ( (( 𝐴 𝐹 𝐵 )) ∈ 𝐶 → ( 𝐴 ∈ V ∧ 𝐵 ∈ V ) )

Proof

Step Hyp Ref Expression
1 aovprc.1 Rel dom 𝐹
2 df-aov (( 𝐴 𝐹 𝐵 )) = ( 𝐹 ''' ⟨ 𝐴 , 𝐵 ⟩ )
3 2 eleq1i ( (( 𝐴 𝐹 𝐵 )) ∈ 𝐶 ↔ ( 𝐹 ''' ⟨ 𝐴 , 𝐵 ⟩ ) ∈ 𝐶 )
4 afvvdm ( ( 𝐹 ''' ⟨ 𝐴 , 𝐵 ⟩ ) ∈ 𝐶 → ⟨ 𝐴 , 𝐵 ⟩ ∈ dom 𝐹 )
5 df-br ( 𝐴 dom 𝐹 𝐵 ↔ ⟨ 𝐴 , 𝐵 ⟩ ∈ dom 𝐹 )
6 1 brrelex12i ( 𝐴 dom 𝐹 𝐵 → ( 𝐴 ∈ V ∧ 𝐵 ∈ V ) )
7 5 6 sylbir ( ⟨ 𝐴 , 𝐵 ⟩ ∈ dom 𝐹 → ( 𝐴 ∈ V ∧ 𝐵 ∈ V ) )
8 4 7 syl ( ( 𝐹 ''' ⟨ 𝐴 , 𝐵 ⟩ ) ∈ 𝐶 → ( 𝐴 ∈ V ∧ 𝐵 ∈ V ) )
9 3 8 sylbi ( (( 𝐴 𝐹 𝐵 )) ∈ 𝐶 → ( 𝐴 ∈ V ∧ 𝐵 ∈ V ) )