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(*         *   The Coq Proof Assistant / The Coq Development Team       *)
(*  v      *   INRIA, CNRS and contributors - Copyright 1999-2018       *)
(* <O___,, *       (see CREDITS file for the list of authors)           *)
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(*    //   *    This file is distributed under the terms of the         *)
(*         *     GNU Lesser General Public License Version 2.1          *)
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Local Open Scope R_scope.

(** Division *)
Theorem derivable_pt_lim_div :
forall (f1 f2:R -> R) (x l1 l2:R),
derivable_pt_lim f1 x l1 ->
derivable_pt_lim f2 x l2 ->
f2 x <> 0 ->
derivable_pt_lim (f1 / f2) x ((l1 * f2 x - l2 * f1 x) / Rsqr (f2 x)).