proposition: Lemma det_cyclique (p q r : Plane) : det p q r = det q r p.
proof: Proof. by rewrite !develop_det; ring. Qed.
imports: axiomsKnuth mathcomp(all_ssreflect ssralg matrix ssrnum vector reals) mathcomp(normedtype order) mathcomp.algebra_tactics(ring) mathcomp.zify(zify)