proposition: Lemma le_0_IZR : forall n:Z, 0 <= IZR n -> (0 <= n)%Z.
proof: Proof. unfold Rle; intros n [H | ->%eq_sym%eq_IZR_R0]. - now apply Z.lt_le_incl, lt_0_IZR. - now apply Z.le_refl. Qed.
imports: RelationClasses Raxioms Rpow_def ZArith ZArithRing RealField