proposition: Lemma Rmult_ge_compat_r : forall r r1 r2, r >= 0 -> r1 >= r2 -> r1 * r >= r2 * r.
proof: Proof. now intros r r1 r2; rewrite 2(Rmult_comm _ r); apply Rmult_ge_compat_l. Qed.
imports: RelationClasses Raxioms Rpow_def ZArith ZArithRing RealField