#[global]
Instance CR_cv_morph
: forall {R : ConstructiveReals} (un : nat -> CRcarrier R), CMorphisms.Proper
(CMorphisms.respectful (CReq R) CRelationClasses.iffT) (CR_cv R un).

Lemma CR_cv_le : forall {R : ConstructiveReals}
(u v : nat -> CRcarrier R) (a b : CRcarrier R),
(forall n:nat, u n <= v n)
-> CR_cv R u a
-> CR_cv R v b
-> a <= b.