Metamath Proof Explorer


Theorem cnvnonrel

Description: The converse of the non-relation part of a class is empty. (Contributed by RP, 18-Oct-2020)

Ref Expression
Assertion cnvnonrel ◡ ( 𝐴 ∖ ◡ ◡ 𝐴 ) = ∅

Proof

Step Hyp Ref Expression
1 cnvdif ⊢ ◡ ( 𝐴 ∖ ◡ ◡ 𝐴 ) = ( ◡ 𝐴 ∖ ◡ ◡ ◡ 𝐴 )
2 relcnv ⊢ Rel ◡ 𝐴
3 relnonrel ⊢ ( Rel ◡ 𝐴 ↔ ( ◡ 𝐴 ∖ ◡ ◡ ◡ 𝐴 ) = ∅ )
4 2 3 mpbi ⊢ ( ◡ 𝐴 ∖ ◡ ◡ ◡ 𝐴 ) = ∅
5 1 4 eqtri ⊢ ◡ ( 𝐴 ∖ ◡ ◡ 𝐴 ) = ∅