proposition: Lemma Rge_gt_dec : forall r1 r2, {r1 >= r2} + {r2 > r1}.
proof: Proof. intros r1 r2; destruct (Rle_dec r2 r1) as [Hle | H%Rnot_le_lt]. - now left; apply Rle_ge. - now right; apply Rlt_gt. Qed.
imports: RelationClasses Raxioms Rpow_def ZArith ZArithRing RealField