Description: Trichotomy law for strict orderings. (Contributed by Scott Fenton, 8-Dec-2021)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | sotrine | |- ( ( R Or A /\ ( B e. A /\ C e. A ) ) -> ( B =/= C <-> ( B R C \/ C R B ) ) ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | sotrieq | |- ( ( R Or A /\ ( B e. A /\ C e. A ) ) -> ( B = C <-> -. ( B R C \/ C R B ) ) ) |
|
| 2 | 1 | bicomd | |- ( ( R Or A /\ ( B e. A /\ C e. A ) ) -> ( -. ( B R C \/ C R B ) <-> B = C ) ) |
| 3 | 2 | necon1abid | |- ( ( R Or A /\ ( B e. A /\ C e. A ) ) -> ( B =/= C <-> ( B R C \/ C R B ) ) ) |