proposition: Lemma pos_mult_rev_r x y : 0 < x * y → 0 < x → 0 < y.
proof: Proof. intros. apply pos_mult_rev_l with x. now rewrite commutativity. easy. Qed.
imports: Coq.setoid_ring.Ring MathClasses.interfaces.abstract_algebra MathClasses.interfaces.orders MathClasses.theory.rings MathClasses.orders.orders MathClasses.orders.maps