proposition: Lemma Rge_lt_dec : forall r1 r2, {r1 >= r2} + {r1 < r2}.
proof: Proof. intros r1 r2; destruct (Rge_gt_dec r1 r2) as [Hge | H%Rgt_lt]. - now left. - now right. Qed.
imports: RelationClasses Raxioms Rpow_def ZArith ZArithRing RealField