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 |
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 |