Metamath Proof Explorer


Theorem rncnvcnv

Description: The range of the double converse of a class is equal to its range (even when that class in not a relation). (Contributed by NM, 8-Apr-2007)

Ref Expression
Assertion rncnvcnv ran ◡ ◡ 𝐴 = ran 𝐴

Proof

Step Hyp Ref Expression
1 df-rn ⊢ ran 𝐴 = dom ◡ 𝐴
2 dfdm4 ⊢ dom ◡ 𝐴 = ran ◡ ◡ 𝐴
3 1 2 eqtr2i ⊢ ran ◡ ◡ 𝐴 = ran 𝐴