(* For consistency with Rplus_opp_r and Rplus_opp_l. *)
Definition Rmult_inv_r := Rinv_r.Definition Rmult_inv_l := Rinv_l.

Lemma Rplus_minus_swap : forall r1 r2 r3, (r1 + r2) - r3 = (r1 - r3) + r2.