Lemma multdivNonnegativeRationals : ∏ q r : NonnegativeRationals, 0 < r -> r * (q / r) = q. Proof. intros q r Hr0. unfold divNonnegativeRationals. rewrite iscomm_multNonnegativeRationals, isassoc_multNonnegativeRationals. rewrite islinv_NonnegativeRationals. - now apply isrunit_oneNonnegativeRationals. - exact Hr0. 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.