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