proposition: Lemma abs_gt_0 : forall x : K, x <> zero -> 0 < abs x.
proof: Proof. intros x Hx. apply Rnot_le_lt. contradict Hx. apply abs_eq_zero. apply Rle_antisym with (1 := Hx). apply abs_ge_0. Qed.
imports: Coq(Reals Psatz ssreflect) Rcomplements Rbar Markov Iter Lub