proposition: Lemma ratMult_small_le : forall r1 r2, r2 <= 1 -> r1 * r2 <= r1.
proof: Proof. rattac. inversion H0; clear H0; subst. rewrite Nat.mul_1_r in l. rewrite Nat.mul_1_l in l. rewrite Nat.mul_assoc. rewrite <- (Nat.mul_assoc n2). rewrite (Nat.mul_comm n). rewrite Nat.mul_assoc. apply Nat.mul_le_mono; auto. Qed.
imports: micromega.Lia List FCF.StdNat Arith Lia Setoid RelationClasses Coq.Classes.Morphisms