proposition: Lemma CRplus_neg_rat_lt : forall {R : ConstructiveReals} (x : CRcarrier R) (q : Q), Qlt q 0 -> CRlt R (CRplus R x (CR_of_Q R q)) x.
proof: Proof. intros. apply (CRlt_le_trans _ (CRplus R x 0)). 2: apply CRplus_0_r. apply CRplus_lt_compat_l. apply (CRlt_le_trans _ (CR_of_Q R 0)). - apply CR_of_Q_lt. exact H. - apply CRle_refl. Qed.
imports: QArith Qabs ConstructiveReals ConstructiveLimits ConstructiveAbs