proposition: Lemma Rlt_pos_pos_Rdiv: forall r1 r2 : R, 0 < r1 -> 0 < r2 / r1 -> 0< r2.
proof: Proof. intros r1 r2 Hr2 Hr12; unfold Rdiv in Hr12; apply Rlt_pos_pos_Rmult with (/r1); auto. Qed.
imports: Coq(Reals) Coq(Lra) Coq(Fourier) Coq(Euclid) Coq(Lia)