--- /dev/null
+(**************************************************************************)
+(* ___ *)
+(* ||M|| *)
+(* ||A|| A project by Andrea Asperti *)
+(* ||T|| *)
+(* ||I|| Developers: *)
+(* ||T|| The HELM team. *)
+(* ||A|| http://helm.cs.unibo.it *)
+(* \ / *)
+(* \ / This file is distributed under the terms of the *)
+(* v GNU General Public License Version 2 *)
+(* *)
+(**************************************************************************)
+
+(* This file was automatically generated: do not edit *********************)
+
+set "baseuri" "cic:/matita/CoRN-Decl/transc/Pi".
+
+include "CoRN.ma".
+
+include "transc/SinCos.ma".
+
+(* UNEXPORTED
+Section Properties_of_Pi
+*)
+
+(*#* printing Pi %\ensuremath{\pi}% #π# *)
+
+(*#* **Definition of Pi
+
+[Pi] is defined as twice the first positive zero of the cosine. In order to do this, we follow the construction described in Bishop 1969, section 7.
+*)
+
+inline "cic:/CoRN/transc/Pi/pi_seq.con".
+
+(* UNEXPORTED
+Opaque Cosine.
+*)
+
+(* begin hide *)
+
+(* UNEXPORTED
+Opaque Sine.
+*)
+
+inline "cic:/CoRN/transc/Pi/pi_seq_lemma.con".
+
+(* end hide *)
+
+(*#*
+This sequence is nonnegative and the cosine of any number between
+[Zero] and any of its values is strictly positive; therefore the
+sequence is strictly increasing.
+*)
+
+inline "cic:/CoRN/transc/Pi/pi_seq_nonneg.con".
+
+inline "cic:/CoRN/transc/Pi/cos_pi_seq_pos.con".
+
+inline "cic:/CoRN/transc/Pi/pi_seq_incr.con".
+
+(*#* Trivial---but useful---consequences. *)
+
+inline "cic:/CoRN/transc/Pi/sin_pi_seq_mon.con".
+
+inline "cic:/CoRN/transc/Pi/sin_pi_seq_nonneg.con".
+
+inline "cic:/CoRN/transc/Pi/sin_pi_seq_gt_one.con".
+
+inline "cic:/CoRN/transc/Pi/cos_pi_seq_mon.con".
+
+(* begin hide *)
+
+inline "cic:/CoRN/transc/Pi/pi_seq_gt_one.con".
+
+(* UNEXPORTED
+Opaque Sine Cosine.
+*)
+
+inline "cic:/CoRN/transc/Pi/pi_seq_bnd.con".
+
+inline "cic:/CoRN/transc/Pi/pi_seq_bnd'.con".
+
+inline "cic:/CoRN/transc/Pi/pi_seq_bnd''.con".
+
+(* end hide *)
+
+(*#* An auxiliary result. *)
+
+inline "cic:/CoRN/transc/Pi/Sin_One_pos.con".
+
+(*#* We can now prove that this is a Cauchy sequence. We define [Pi] as
+twice its limit.
+*)
+
+inline "cic:/CoRN/transc/Pi/pi_seq_Cauchy.con".
+
+inline "cic:/CoRN/transc/Pi/Pi.con".
+
+(*#*
+For $x\in[0,\frac{\pi}2)$#x∈[0,π/2)#, [(Cos x) [>] 0];
+$\cos(\frac{pi}2)=0$#cos(π/2)=0#.
+*)
+
+inline "cic:/CoRN/transc/Pi/pos_cos.con".
+
+inline "cic:/CoRN/transc/Pi/Cos_HalfPi.con".
+
+(*#* Convergence to [Pi [/] Two] is increasing; therefore, [Pi] is positive. *)
+
+inline "cic:/CoRN/transc/Pi/HalfPi_gt_pi_seq.con".
+
+inline "cic:/CoRN/transc/Pi/pos_Pi.con".
+
+(* UNEXPORTED
+End Properties_of_Pi
+*)
+
+(* UNEXPORTED
+Hint Resolve Cos_HalfPi: algebra.
+*)
+
+(* UNEXPORTED
+Section Pi_and_Order
+*)
+
+(*#* **Properties of Pi
+
+The following are trivial ordering properties of multiples of [Pi]
+that will be used so often that it is convenient to state as lemmas;
+also, we define a hint database that automatically tries to apply this
+lemmas, to make proof development easier.
+
+A summary of what is being proved is simply:
+[[
+[--]Pi [<] [--]Pi[/]Two [<] [--] Pi[/]Four [<] Zero [<] Pi[/]Four [<] Pi[/]Two [<] Pi
+]]
+
+[PiSolve] will prove any of these inequalities.
+*)
+
+inline "cic:/CoRN/transc/Pi/pos_HalfPi.con".
+
+inline "cic:/CoRN/transc/Pi/pos_QuarterPi.con".
+
+inline "cic:/CoRN/transc/Pi/QuarterPi_less_HalfPi.con".
+
+inline "cic:/CoRN/transc/Pi/HalfPi_less_Pi.con".
+
+inline "cic:/CoRN/transc/Pi/QuarterPi_less_Pi.con".
+
+inline "cic:/CoRN/transc/Pi/neg_invPi.con".
+
+inline "cic:/CoRN/transc/Pi/neg_invHalfPi.con".
+
+inline "cic:/CoRN/transc/Pi/neg_invQuarterPi.con".
+
+inline "cic:/CoRN/transc/Pi/invHalfPi_less_invQuarterPi.con".
+
+inline "cic:/CoRN/transc/Pi/invPi_less_invHalfPi.con".
+
+inline "cic:/CoRN/transc/Pi/invPi_less_invQuarterPi.con".
+
+inline "cic:/CoRN/transc/Pi/invPi_less_Pi.con".
+
+inline "cic:/CoRN/transc/Pi/invPi_less_HalfPi.con".
+
+inline "cic:/CoRN/transc/Pi/invPi_less_QuarterPi.con".
+
+inline "cic:/CoRN/transc/Pi/invHalfPi_less_Pi.con".
+
+inline "cic:/CoRN/transc/Pi/invHalfPi_less_HalfPi.con".
+
+inline "cic:/CoRN/transc/Pi/invHalfPi_less_QuarterPi.con".
+
+inline "cic:/CoRN/transc/Pi/invQuarterPi_less_Pi.con".
+
+inline "cic:/CoRN/transc/Pi/invQuarterPi_less_HalfPi.con".
+
+inline "cic:/CoRN/transc/Pi/invQuarterPi_less_QuarterPi.con".
+
+(* UNEXPORTED
+End Pi_and_Order
+*)
+
+(* UNEXPORTED
+Hint Resolve pos_Pi pos_HalfPi pos_QuarterPi QuarterPi_less_HalfPi
+ HalfPi_less_Pi QuarterPi_less_Pi neg_invPi neg_invHalfPi neg_invQuarterPi
+ invHalfPi_less_invQuarterPi invPi_less_invHalfPi invPi_less_invQuarterPi
+ invPi_less_Pi invPi_less_HalfPi invPi_less_QuarterPi invHalfPi_less_Pi
+ invHalfPi_less_HalfPi invHalfPi_less_QuarterPi invQuarterPi_less_Pi
+ invQuarterPi_less_HalfPi invQuarterPi_less_QuarterPi: piorder.
+*)
+
+(* begin hide *)
+
+(* UNEXPORTED
+Ltac PiSolve := try apply less_leEq; auto with piorder.
+*)
+
+(* end hide *)
+
+(* UNEXPORTED
+Section Sin_And_Cos
+*)
+
+(*#* **More formulas
+
+We now move back to trigonometric identities: sine, cosine and tangent of
+the double.
+*)
+
+inline "cic:/CoRN/transc/Pi/Cos_double.con".
+
+inline "cic:/CoRN/transc/Pi/Sin_double.con".
+
+inline "cic:/CoRN/transc/Pi/Tan_double.con".
+
+(* begin hide *)
+
+inline "cic:/CoRN/transc/Pi/sqrt_lemma.con".
+
+(* end hide *)
+
+(*#* Value of trigonometric functions at [Pi[/]Four]. *)
+
+inline "cic:/CoRN/transc/Pi/Cos_QuarterPi.con".
+
+inline "cic:/CoRN/transc/Pi/Sin_QuarterPi.con".
+
+(* UNEXPORTED
+Hint Resolve Sin_QuarterPi Cos_QuarterPi: algebra.
+*)
+
+(* UNEXPORTED
+Opaque Sine Cosine.
+*)
+
+inline "cic:/CoRN/transc/Pi/Tan_QuarterPi.con".
+
+(*#* Shifting sine and cosine by [Pi[/]Two] and [Pi]. *)
+
+inline "cic:/CoRN/transc/Pi/Sin_HalfPi.con".
+
+(* UNEXPORTED
+Hint Resolve Sin_HalfPi: algebra.
+*)
+
+inline "cic:/CoRN/transc/Pi/Sin_plus_HalfPi.con".
+
+inline "cic:/CoRN/transc/Pi/Sin_HalfPi_minus.con".
+
+inline "cic:/CoRN/transc/Pi/Cos_plus_HalfPi.con".
+
+inline "cic:/CoRN/transc/Pi/Cos_HalfPi_minus.con".
+
+inline "cic:/CoRN/transc/Pi/Sin_Pi.con".
+
+inline "cic:/CoRN/transc/Pi/Cos_Pi.con".
+
+inline "cic:/CoRN/transc/Pi/Sin_plus_Pi.con".
+
+inline "cic:/CoRN/transc/Pi/Cos_plus_Pi.con".
+
+(* UNEXPORTED
+Hint Resolve Sin_plus_Pi Cos_plus_Pi: algebra.
+*)
+
+(*#* Sine and cosine have period [Two Pi], tangent has period [Pi]. *)
+
+inline "cic:/CoRN/transc/Pi/Sin_periodic.con".
+
+inline "cic:/CoRN/transc/Pi/Cos_periodic.con".
+
+inline "cic:/CoRN/transc/Pi/Tan_periodic.con".
+
+(* UNEXPORTED
+End Sin_And_Cos
+*)
+
+(* UNEXPORTED
+Hint Resolve Cos_double Sin_double Tan_double Cos_QuarterPi Sin_QuarterPi
+ Tan_QuarterPi Sin_Pi Cos_Pi Sin_HalfPi Sin_plus_HalfPi Sin_HalfPi_minus
+ Cos_plus_HalfPi Cos_HalfPi_minus Sin_plus_Pi Cos_plus_Pi Sin_periodic
+ Cos_periodic Tan_periodic: algebra.
+*)
+
projects / helm.git / blobdiff