induction n1; intuition; simpl in *.
eapply expRat_le_1; trivial.
destruct n2;
simpl.
omega.
eapply ratMult_leRat_compat.
intuition.
eapply IHn1.
trivial.
omega.
Qed.

(* Specifications: *)
Lemma expRat_leRat_compat : forall n r1 r2,
r1 <= r2 ->
expRat r1 n <= expRat r2 n.