Lemma ispositive_plusNonnegativeRationals_l : ∏ x y : NonnegativeRationals, 0 < x -> 0 < x + y. Proof. intros x y Hx. apply istrans_lt_le_ltNonnegativeRationals with x. - exact Hx. - now apply plusNonnegativeRationals_le_r. Qed.
Require Import UniMath.MoreFoundations.Tactics. Require Import UniMath.MoreFoundations.PartA. Require Import UniMath.MoreFoundations.Sets. Require Import UniMath.MoreFoundations.Orders. Require Import UniMath.RealNumbers.Sets. Require Import UniMath.RealNumbers.Fields. Require Import UniMath.OrderTheory.Lattice.Lattice. Require Import UniMath.RealNumbers.Prelim.