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(*         *   The Coq Proof Assistant / The Coq Development Team       *)
(*  v      *   INRIA, CNRS and contributors - Copyright 1999-2018       *)
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(*         *     GNU Lesser General Public License Version 2.1          *)
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Local Open Scope R_scope.

(** sqrt is derivable for all x>0 *)
Lemma derivable_pt_lim_sqrt :
forall x:R, 0 < x -> derivable_pt_lim sqrt x (/ (2 * sqrt x)).