proposition: Lemma islinv_CDRinv : ∏ (x : X) (Hx0 : x ≠ (0 : X)), (CDRinv x Hx0) * x = 1.
proof: Proof. intros x Hx0. apply (pr1 (pr2 (pr2 (pr2 (pr2 (pr2 (pr2 X)))) x Hx0))). Qed.
imports: UniMath.Algebra.DivisionRig UniMath.Algebra.Domains_and_Fields UniMath.Algebra.Apartness UniMath.MoreFoundations.Tactics