proposition: Lemma Bounded_T_me_mf_g_h_nonzero:forall a b c d e f g h,Bounded_T (((a,b),(c,d)),((e,f),(g,h))) -> (g - e + (h - f)) <> Zero.
proof: Proof. intros a b c d e f g h [[H1 [H2 [H3 H4]]]|[H1 [H2 [H3 H4]]]]; unfold fst, snd in H1; unfold fst, snd in H2; unfold fst, snd in H3; unfold fst, snd in H4; stepl (- e - f + g + h); auto; try ring; apply sym_not_eq; auto. Qed.
imports: digits Bounded_M Raxioms RIneq QArithSternBrocot(R_addenda) Fourier_solvable_ineqs