proposition: Theorem ratDistance_le_trans : forall r1 r2 r3 d1 d2, ratDistance r1 r2 <= d1 -> ratDistance r2 r3 <= d2 -> ratDistance r1 r3 <= d1 + d2.
proof: Proof. intuition. eapply leRat_trans. eapply ratTriangleInequality. eapply ratAdd_leRat_compat; eauto. Qed.
imports: micromega.Lia List FCF.StdNat Arith Lia Setoid RelationClasses Coq.Classes.Morphisms