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15 (* This file was automatically generated: do not edit *********************)
17 set "baseuri" "cic:/matita/CoRN-Decl/ftc/CalculusTheorems".
19 (* $Id: CalculusTheorems.v,v 1.6 2004/04/23 10:00:57 lcf Exp $ *)
34 Section Various_Theorems.
37 (*#* *Calculus Theorems
39 This file is intended to present a collection of miscellaneous, mostly
40 technical results in differential calculus that are interesting or
41 useful in future work.
43 We begin with some properties of continuous functions. Every
44 continuous function commutes with the limit of a numerical sequence
45 (sometimes called Heine continuity).
48 inline cic:/CoRN/ftc/CalculusTheorems/Continuous_imp_comm_Lim.con.
51 This is a tricky result: if [F] is continuous and positive in both [[a,b]]
52 and [(b,c]], then it is positive in [[a,c]].
55 inline cic:/CoRN/ftc/CalculusTheorems/Continuous_imp_pos.con.
58 Similar results for increasing functions:
61 inline cic:/CoRN/ftc/CalculusTheorems/strict_inc_glues.con.
63 inline cic:/CoRN/ftc/CalculusTheorems/strict_inc_glues'.con.
65 inline cic:/CoRN/ftc/CalculusTheorems/strict_dec_glues.con.
67 inline cic:/CoRN/ftc/CalculusTheorems/strict_dec_glues'.con.
69 (*#* More on glueing intervals. *)
71 inline cic:/CoRN/ftc/CalculusTheorems/olor_pos_clor_nonneg.con.
73 inline cic:/CoRN/ftc/CalculusTheorems/olor_pos_olcr_nonneg.con.
75 inline cic:/CoRN/ftc/CalculusTheorems/olor_pos_clcr_nonneg.con.
78 Any function that has the null function as its derivative must be constant.
81 inline cic:/CoRN/ftc/CalculusTheorems/FConst_prop.con.
83 (*#* As a corollary, two functions with the same derivative must differ
87 inline cic:/CoRN/ftc/CalculusTheorems/Feq_crit_with_const.con.
89 (*#* This yields the following known result: any differential equation
90 of the form [f'=g] with initial condition [f(a) [=] b] has a unique solution.
93 inline cic:/CoRN/ftc/CalculusTheorems/Feq_criterium.con.
96 Finally, a well known result: any function with a (strictly) positive
97 derivative is (strictly) increasing. Although the two lemmas look
98 quite similar the proofs are completely different, both from the
99 formalization and from the mathematical point of view.
102 inline cic:/CoRN/ftc/CalculusTheorems/Derivative_imp_resp_less.con.
104 inline cic:/CoRN/ftc/CalculusTheorems/Derivative_imp_resp_leEq.con.
106 inline cic:/CoRN/ftc/CalculusTheorems/Derivative_imp_resp_less'.con.
108 (*#* From these results we can finally prove that exponentiation to a
109 real power preserves the less or equal than relation!
120 inline cic:/CoRN/ftc/CalculusTheorems/nexp_resp_leEq_odd.con.
123 End Various_Theorems.