Description: The converse of a set is an element of the class of relations. (Contributed by Peter Mazsa, 18-Aug-2019)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | cnvelrels | |- ( A e. V -> `' A e. Rels ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | relcnv | |- Rel `' A |
|
| 2 | cnvexg | |- ( A e. V -> `' A e. _V ) |
|
| 3 | elrelsrel | |- ( `' A e. _V -> ( `' A e. Rels <-> Rel `' A ) ) |
|
| 4 | 2 3 | syl | |- ( A e. V -> ( `' A e. Rels <-> Rel `' A ) ) |
| 5 | 1 4 | mpbiri | |- ( A e. V -> `' A e. Rels ) |