proposition: Lemma scalar_product_rotate (p q : Plane) : scalar_product (rotate p) (rotate q) = scalar_product p q.
proof: Proof. by rewrite/scalar_product/rotate/=; ring. Qed.
imports: axiomsKnuth mathcomp(all_ssreflect ssralg matrix ssrnum vector reals) mathcomp(normedtype order) mathcomp.algebra_tactics(ring) mathcomp.zify(zify)