Metamath Proof Explorer


Theorem ndmaov

Description: The value of an operation outside its domain, analogous to ndmafv . (Contributed by Alexander van der Vekens, 26-May-2017)

Ref Expression
Assertion ndmaov ( ¬ ⟨ 𝐴 , 𝐵 ⟩ ∈ dom 𝐹 → (( 𝐴 𝐹 𝐵 )) = V )

Proof

Step Hyp Ref Expression
1 df-aov (( 𝐴 𝐹 𝐵 )) = ( 𝐹 ''' ⟨ 𝐴 , 𝐵 ⟩ )
2 ndmafv ( ¬ ⟨ 𝐴 , 𝐵 ⟩ ∈ dom 𝐹 → ( 𝐹 ''' ⟨ 𝐴 , 𝐵 ⟩ ) = V )
3 1 2 syl5eq ( ¬ ⟨ 𝐴 , 𝐵 ⟩ ∈ dom 𝐹 → (( 𝐴 𝐹 𝐵 )) = V )