Description: Two ways of saying a relation is transitive. Special instance of cotr2g . (Contributed by RP, 22-Mar-2020)
| Ref | Expression | ||
|---|---|---|---|
| Hypotheses | cotr2.a | |- dom R C_ A |
|
| cotr2.b | |- ( dom R i^i ran R ) C_ B |
||
| cotr2.c | |- ran R C_ C |
||
| Assertion | cotr2 | |- ( ( R o. R ) C_ R <-> A. x e. A A. y e. B A. z e. C ( ( x R y /\ y R z ) -> x R z ) ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | cotr2.a | |- dom R C_ A |
|
| 2 | cotr2.b | |- ( dom R i^i ran R ) C_ B |
|
| 3 | cotr2.c | |- ran R C_ C |
|
| 4 | incom | |- ( dom R i^i ran R ) = ( ran R i^i dom R ) |
|
| 5 | 4 2 | eqsstrri | |- ( ran R i^i dom R ) C_ B |
| 6 | 1 5 3 | cotr2g | |- ( ( R o. R ) C_ R <-> A. x e. A A. y e. B A. z e. C ( ( x R y /\ y R z ) -> x R z ) ) |