proposition: Lemma CReal_mult_lt_reg_l : forall r r1 r2, 0 < r -> r * r1 < r * r2 -> r1 < r2.
proof: Proof. intros z x y H H0. apply (CReal_mult_lt_compat_l ((/z) (inr H))) in H0. - repeat rewrite <- CReal_mult_assoc in H0. rewrite CReal_inv_l in H0. repeat rewrite CReal_mult_1_l in H0. apply H0. - apply CReal_inv_0_lt_compat. exact H. Qed.
imports: QArith Qabs Qround Qpower Logic.ConstructiveEpsilon ConstructiveCauchyReals Lia Lqa QExtra