Description: Rotation law for triple conjunction. (Contributed by NM, 8-Apr-1994) (Proof shortened by Wolf Lammen, 9-Jun-2022)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | 3anrot | |- ( ( ph /\ ps /\ ch ) <-> ( ps /\ ch /\ ph ) ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | 3ancoma | |- ( ( ph /\ ps /\ ch ) <-> ( ps /\ ph /\ ch ) ) |
|
| 2 | 3ancomb | |- ( ( ps /\ ph /\ ch ) <-> ( ps /\ ch /\ ph ) ) |
|
| 3 | 1 2 | bitri | |- ( ( ph /\ ps /\ ch ) <-> ( ps /\ ch /\ ph ) ) |