Description: The cosets by the identity relation are in equivalence relation if and only if the identity relation is disjoint. (Contributed by Peter Mazsa, 31-Dec-2021)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | detid | |- ( Disj _I <-> EqvRel ,~ _I ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | disjALTVid | |- Disj _I |
|
| 2 | 1 | detlem | |- ( Disj _I <-> EqvRel ,~ _I ) |