proposition: Lemma lemma_ray2 : forall A B C, Out A B C -> neq A B.
proof: Proof. intros. let Tf:=fresh in assert (Tf:exists E, (BetS E A C /\ BetS E A B)) by (conclude_def Out );destruct Tf as [E];spliter. assert (neq A B) by (forward_using lemma_betweennotequal). close. Qed.
imports: GeoCoq.Elements.OriginalProofs.lemma_betweennotequal