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(*         *   The Coq Proof Assistant / The Coq Development Team       *)
(*  v      *   INRIA, CNRS and contributors - Copyright 1999-2018       *)
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(*    //   *    This file is distributed under the terms of the         *)
(*         *     GNU Lesser General Public License Version 2.1          *)
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(** * An absolute value for normalized rational numbers. *)
(** Contributed by Cédric Auger *)

Lemma Qcabs_canon (x : Q) : Qred x = x -> Qred (Qabs x) = Qabs x.