1 (**************************************************************************)
4 (* ||A|| A project by Andrea Asperti *)
6 (* ||I|| Developers: *)
7 (* ||T|| The HELM team. *)
8 (* ||A|| http://helm.cs.unibo.it *)
10 (* \ / This file is distributed under the terms of the *)
11 (* v GNU General Public License Version 2 *)
13 (**************************************************************************)
15 (* This file was automatically generated: do not edit *********************)
17 set "baseuri" "cic:/matita/CoRN-Decl/ftc/CalculusTheorems".
21 (* $Id: CalculusTheorems.v,v 1.6 2004/04/23 10:00:57 lcf Exp $ *)
23 include "ftc/Rolle.ma".
25 include "tactics/DiffTactics3.ma".
32 Section Various_Theorems
35 (*#* *Calculus Theorems
37 This file is intended to present a collection of miscellaneous, mostly
38 technical results in differential calculus that are interesting or
39 useful in future work.
41 We begin with some properties of continuous functions. Every
42 continuous function commutes with the limit of a numerical sequence
43 (sometimes called Heine continuity).
46 inline "cic:/CoRN/ftc/CalculusTheorems/Continuous_imp_comm_Lim.con".
49 This is a tricky result: if [F] is continuous and positive in both [[a,b]]
50 and [(b,c]], then it is positive in [[a,c]].
53 inline "cic:/CoRN/ftc/CalculusTheorems/Continuous_imp_pos.con".
56 Similar results for increasing functions:
59 inline "cic:/CoRN/ftc/CalculusTheorems/strict_inc_glues.con".
61 inline "cic:/CoRN/ftc/CalculusTheorems/strict_inc_glues'.con".
63 inline "cic:/CoRN/ftc/CalculusTheorems/strict_dec_glues.con".
65 inline "cic:/CoRN/ftc/CalculusTheorems/strict_dec_glues'.con".
67 (*#* More on glueing intervals. *)
69 inline "cic:/CoRN/ftc/CalculusTheorems/olor_pos_clor_nonneg.con".
71 inline "cic:/CoRN/ftc/CalculusTheorems/olor_pos_olcr_nonneg.con".
73 inline "cic:/CoRN/ftc/CalculusTheorems/olor_pos_clcr_nonneg.con".
76 Any function that has the null function as its derivative must be constant.
79 inline "cic:/CoRN/ftc/CalculusTheorems/FConst_prop.con".
81 (*#* As a corollary, two functions with the same derivative must differ
85 inline "cic:/CoRN/ftc/CalculusTheorems/Feq_crit_with_const.con".
87 (*#* This yields the following known result: any differential equation
88 of the form [f'=g] with initial condition [f(a) [=] b] has a unique solution.
91 inline "cic:/CoRN/ftc/CalculusTheorems/Feq_criterium.con".
94 Finally, a well known result: any function with a (strictly) positive
95 derivative is (strictly) increasing. Although the two lemmas look
96 quite similar the proofs are completely different, both from the
97 formalization and from the mathematical point of view.
100 inline "cic:/CoRN/ftc/CalculusTheorems/Derivative_imp_resp_less.con".
102 inline "cic:/CoRN/ftc/CalculusTheorems/Derivative_imp_resp_leEq.con".
104 inline "cic:/CoRN/ftc/CalculusTheorems/Derivative_imp_resp_less'.con".
106 (*#* From these results we can finally prove that exponentiation to a
107 real power preserves the less or equal than relation!
118 inline "cic:/CoRN/ftc/CalculusTheorems/nexp_resp_leEq_odd.con".