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(* as published by the Free Software Foundation; either version 2.1   *)
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(* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the      *)
(* GNU General Public License for more details.                       *)
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(* 02110-1301 USA                                                     *)
Require Export Q_field.
intros n m; case m; case n; auto; intros n' m'; simpl in |- *;
rewrite Qpositive_mult_sym; auto.
Qed.
intros n m p; case p; case m; case n; auto; intros n' m' p'; simpl in |- *;
rewrite Qpositive_mult_assoc; auto.
Qed.

Theorem Qplus_zero_left : forall n : Q, Qplus Zero n = n.