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/transc/RealPowers".
21 (* $Id: RealPowers.v,v 1.5 2004/04/23 10:01:08 lcf Exp $ *)
23 (*#* printing [!] %\ensuremath{\hat{\ }}% #^# *)
25 (*#* printing {!} %\ensuremath{\hat{\ }}% #^# *)
27 include "transc/Exponential.ma".
33 (*#* *Arbitrary Real Powers
35 **Powers of Real Numbers
38 $x^y=e^{y\times\log(x)}$#x<sup>y</sup>=e<sup>y*log(x)</sup>#, whenever
39 [x [>] 0], inspired by the rules for manipulating these expressions.
42 inline "cic:/CoRN/transc/RealPowers/power.con".
45 Notation "x [!] y [//] Hy" := (power x y Hy) (at level 20).
49 This definition yields a well defined, strongly extensional function
50 which extends the algebraic exponentiation to an integer power and
51 still has all the good properties of that operation; when [x [=] e] it
52 coincides with the exponential function.
55 inline "cic:/CoRN/transc/RealPowers/power_wd.con".
57 inline "cic:/CoRN/transc/RealPowers/power_strext.con".
59 inline "cic:/CoRN/transc/RealPowers/power_plus.con".
61 inline "cic:/CoRN/transc/RealPowers/power_inv.con".
64 Hint Resolve power_wd power_plus power_inv: algebra.
67 inline "cic:/CoRN/transc/RealPowers/power_minus.con".
69 inline "cic:/CoRN/transc/RealPowers/power_nat.con".
72 Hint Resolve power_minus power_nat: algebra.
75 inline "cic:/CoRN/transc/RealPowers/power_zero.con".
77 inline "cic:/CoRN/transc/RealPowers/power_one.con".
80 Hint Resolve power_zero power_one: algebra.
87 inline "cic:/CoRN/transc/RealPowers/power_int.con".
90 Hint Resolve power_int: algebra.
93 inline "cic:/CoRN/transc/RealPowers/Exp_power.con".
95 inline "cic:/CoRN/transc/RealPowers/mult_power.con".
97 inline "cic:/CoRN/transc/RealPowers/recip_power.con".
100 Hint Resolve Exp_power mult_power recip_power: algebra.
103 inline "cic:/CoRN/transc/RealPowers/div_power.con".
106 Hint Resolve div_power: algebra.
109 inline "cic:/CoRN/transc/RealPowers/power_ap_zero.con".
111 inline "cic:/CoRN/transc/RealPowers/power_mult.con".
113 inline "cic:/CoRN/transc/RealPowers/power_pos.con".
116 Hint Resolve power_mult: algebra.
119 inline "cic:/CoRN/transc/RealPowers/power_recip.con".
122 Hint Resolve power_recip: algebra.
125 inline "cic:/CoRN/transc/RealPowers/power_div.con".
128 Hint Resolve power_div: algebra.
132 Section Power_Function
135 (*#* **Power Function
137 This operation on real numbers gives birth to an analogous operation
138 on partial functions which preserves continuity.
140 %\begin{convention}% Let [F, G : PartIR].
144 alias id "J" = "cic:/CoRN/transc/RealPowers/Power_Function/J.var".
146 alias id "F" = "cic:/CoRN/transc/RealPowers/Power_Function/F.var".
148 alias id "G" = "cic:/CoRN/transc/RealPowers/Power_Function/G.var".
150 inline "cic:/CoRN/transc/RealPowers/FPower.con".
152 inline "cic:/CoRN/transc/RealPowers/FPower_domain.con".
154 inline "cic:/CoRN/transc/RealPowers/Continuous_power.con".
161 Notation "F {!} G" := (FPower F G) (at level 20).
165 Section More_on_Power_Function
169 Opaque Expon Logarithm.
172 (*#* From global continuity we can obviously get local continuity: *)
174 inline "cic:/CoRN/transc/RealPowers/continuous_I_power.con".
176 (*#* The rule for differentiation is a must. *)
179 Transparent Logarithm.
186 inline "cic:/CoRN/transc/RealPowers/Derivative_power.con".
188 inline "cic:/CoRN/transc/RealPowers/Diffble_power.con".
191 End More_on_Power_Function
195 Hint Resolve Derivative_power: derivate.