Description: Equivalent expressions for an element of the relations class. (Contributed by Peter Mazsa, 21-Jul-2021)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | elrels5 | |- ( R e. V -> ( R e. Rels <-> ( R |` dom R ) = R ) ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | elrelsrel | |- ( R e. V -> ( R e. Rels <-> Rel R ) ) |
|
| 2 | dfrel5 | |- ( Rel R <-> ( R |` dom R ) = R ) |
|
| 3 | 1 2 | bitrdi | |- ( R e. V -> ( R e. Rels <-> ( R |` dom R ) = R ) ) |