proposition: Lemma Rplus_ge_compat_l : forall r r1 r2, r1 >= r2 -> r + r1 >= r + r2.
proof: Proof. now intros r r1 r2 H%Rge_le; apply Rle_ge, Rplus_le_compat_l. Qed.
imports: RelationClasses Raxioms Rpow_def ZArith ZArithRing RealField