Lemma ispositive_multNonnegativeRationals: ∏ x y : NonnegativeRationals, 0 < x -> 0 < y -> 0 < x * y. Proof. intros x y Hx Hy. rewrite <- (israbsorb_zero_multNonnegativeRationals x). apply multNonnegativeRationals_ltcompat_l. + exact Hx. + exact Hy. 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.