proposition: Lemma Bounded_T_denom_nonvanishing_T: forall xi, Bounded_T xi -> (forall x y, (-1 <= x <= 1)%R -> (-1 <= y <= 1)%R -> denom_nonvanishing_T xi x y).
proof: Proof. intros (((a,b),(c,d)),((e,f),(g,h))) H_bounded r Hr; red; simpl; apply Bounded_T_nonzero_denum with a b c d; assumption. Qed.
imports: digits Bounded_M Raxioms RIneq QArithSternBrocot(R_addenda) Fourier_solvable_ineqs