X-Git-Url: http://matita.cs.unibo.it/gitweb/?a=blobdiff_plain;ds=inline;f=helm%2Fsoftware%2Fmatita%2Flibrary%2Fdemo%2Fpower_derivative.ma;h=bca5bbf0181a941d650e4bd24190706673f4ac36;hb=93cc2a2254a2620000377dfc99a7aaedf2b8ec63;hp=e8ab55c3595108eb3e08a8d60c49819752831832;hpb=ca41435a6021292ccba239aa173651c0be705b45;p=helm.git diff --git a/helm/software/matita/library/demo/power_derivative.ma b/helm/software/matita/library/demo/power_derivative.ma index e8ab55c35..bca5bbf01 100644 --- a/helm/software/matita/library/demo/power_derivative.ma +++ b/helm/software/matita/library/demo/power_derivative.ma @@ -24,28 +24,17 @@ axiom Rmult: R→R→R. notation "0" with precedence 89 for @{ 'zero }. -interpretation "Rzero" 'zero = - (cic:/matita/demo/power_derivative/R0.con). -interpretation "Nzero" 'zero = - (cic:/matita/nat/nat/nat.ind#xpointer(1/1/1)). +interpretation "Rzero" 'zero = (R0). +interpretation "Nzero" 'zero = (O). notation "1" with precedence 89 for @{ 'one }. -interpretation "Rone" 'one = - (cic:/matita/demo/power_derivative/R1.con). -interpretation "None" 'one = - (cic:/matita/nat/nat/nat.ind#xpointer(1/1/2) - cic:/matita/nat/nat/nat.ind#xpointer(1/1/1)). +interpretation "Rone" 'one = (R1). +interpretation "None" 'one = (S O). -interpretation "Rplus" 'plus x y = - (cic:/matita/demo/power_derivative/Rplus.con x y). +interpretation "Rplus" 'plus x y = (Rplus x y). -notation "hvbox(a break \middot b)" - left associative with precedence 55 -for @{ 'times $a $b }. - -interpretation "Rmult" 'times x y = - (cic:/matita/demo/power_derivative/Rmult.con x y). +interpretation "Rmult" 'middot x y = (Rmult x y). definition Fplus ≝ λf,g:R→R.λx:R.f x + g x. @@ -53,21 +42,13 @@ definition Fplus ≝ definition Fmult ≝ λf,g:R→R.λx:R.f x · g x. -interpretation "Fplus" 'plus x y = - (cic:/matita/demo/power_derivative/Fplus.con x y). -interpretation "Fmult" 'times x y = - (cic:/matita/demo/power_derivative/Fmult.con x y). +interpretation "Fplus" 'plus x y = (Fplus x y). +interpretation "Fmult" 'middot x y = (Fmult x y). notation "2" with precedence 89 for @{ 'two }. -interpretation "Rtwo" 'two = - (cic:/matita/demo/power_derivative/Rplus.con - cic:/matita/demo/power_derivative/R1.con - cic:/matita/demo/power_derivative/R1.con). -interpretation "Ntwo" 'two = - (cic:/matita/nat/nat/nat.ind#xpointer(1/1/2) - (cic:/matita/nat/nat/nat.ind#xpointer(1/1/2) - (cic:/matita/nat/nat/nat.ind#xpointer(1/1/1)))). +interpretation "Rtwo" 'two = (Rplus R1 R1). +interpretation "Ntwo" 'two = (S (S O)). let rec Rpower (x:R) (n:nat) on n ≝ match n with @@ -75,8 +56,7 @@ let rec Rpower (x:R) (n:nat) on n ≝ | S n ⇒ x · (Rpower x n) ]. -interpretation "Rpower" 'exp x n = - (cic:/matita/demo/power_derivative/Rpower.con x n). +interpretation "Rpower" 'exp x n = (Rpower x n). let rec inj (n:nat) on n : R ≝ match n with @@ -93,13 +73,13 @@ coercion inj. axiom Rplus_Rzero_x: ∀x:R.0+x=x. axiom Rplus_comm: symmetric ? Rplus. axiom Rplus_assoc: associative ? Rplus. -axiom Rmult_Rone_x: ∀x:R.1*x=x. -axiom Rmult_Rzero_x: ∀x:R.0*x=0. +axiom Rmult_Rone_x: ∀x:R.1 · x=x. +axiom Rmult_Rzero_x: ∀x:R.0 · x=0. axiom Rmult_assoc: associative ? Rmult. axiom Rmult_comm: symmetric ? Rmult. axiom Rmult_Rplus_distr: distributive ? Rmult Rplus. -alias symbol "times" = "Rmult". +alias symbol "middot" = "Rmult". alias symbol "plus" = "natural plus". definition monomio ≝ @@ -227,59 +207,61 @@ notation "hvbox('D'[f])" non associative with precedence 90 for @{ 'derivative $f }. -interpretation "Rderivative" 'derivative f = - (cic:/matita/demo/power_derivative/derivative.con f). +interpretation "Rderivative" 'derivative f = (derivative f). -notation "hvbox('x' \sup n)" +(* FG: we definitely do not want 'x' as a keyward! + * Any file that includes this one can not use 'x' as an identifier + *) +notation "hvbox('X' \sup n)" non associative with precedence 60 for @{ 'monomio $n }. -notation "hvbox('x')" +notation "hvbox('X')" non associative with precedence 60 for @{ 'monomio 1 }. -interpretation "Rmonomio" 'monomio n = - (cic:/matita/demo/power_derivative/monomio.con n). +interpretation "Rmonomio" 'monomio n = (monomio n). + +axiom derivative_x0: D[X \sup 0] = 0. +axiom derivative_x1: D[X] = 1. -axiom derivative_x0: D[x \sup 0] = 0. -axiom derivative_x1: D[x] = 1. axiom derivative_mult: ∀f,g:R→R. D[f·g] = D[f]·g + f·D[g]. -alias symbol "times" = "Fmult". +alias symbol "middot" = "Fmult". -theorem derivative_power: ∀n:nat. D[x \sup n] = n·x \sup (pred n). +theorem derivative_power: ∀n:nat. D[X \sup n] = n·X \sup (pred n). assume n:nat. (*we proceed by induction on n to prove - (D[x \sup n] = n · x \sup (pred n)).*) + (D[X \sup n] = n · X \sup (pred n)).*) elim n 0. case O. - the thesis becomes (D[x \sup 0] = 0·x \sup (pred 0)). + the thesis becomes (D[X \sup 0] = 0·X \sup (pred 0)). done. case S (m:nat). by induction hypothesis we know - (D[x \sup m] = m·x \sup (pred m)) (H). + (D[X \sup m] = m·X \sup (pred m)) (H). the thesis becomes - (D[x \sup (1+m)] = (1+m) · x \sup m). + (D[X \sup (1+m)] = (1+m) · X \sup m). we need to prove - (m · (x \sup (1+ pred m)) = m · x \sup m) (Ppred). + (m · (X \sup (1+ pred m)) = m · X \sup m) (Ppred). we proved (0 < m ∨ 0=m) (cases). we proceed by induction on cases - to prove (m · (x \sup (1+ pred m)) = m · x \sup m). + to prove (m · (X \sup (1+ pred m)) = m · X \sup m). case left. suppose (0 < m) (m_pos). using (S_pred ? m_pos) we proved (m = 1 + pred m) (H1). - done. + by H1 done. case right. suppose (0=m) (m_zero). - done. + by m_zero, Fmult_zero_f done. conclude - (D[x \sup (1+m)]) - = (D[x · x \sup m]). - = (D[x] · x \sup m + x · D[x \sup m]). - = (x \sup m + x · (m · x \sup (pred m))) timeout=30. - = (x \sup m + m · (x \sup (1 + pred m))). - = (x \sup m + m · x \sup m). - = ((1+m) · x \sup m) timeout=30 by Fmult_one_f, Fmult_commutative, Fmult_Fplus_distr, costante_sum + (D[X \sup (1+m)]) + = (D[X · X \sup m]). + = (D[X] · X \sup m + X · D[X \sup m]). + = (X \sup m + X · (m · X \sup (pred m))) timeout=30. + = (X \sup m + m · (X \sup (1 + pred m))). + = (X \sup m + m · X \sup m). + = ((1+m) · X \sup m) timeout=30 by Fmult_one_f, Fmult_commutative, Fmult_Fplus_distr, costante_sum done. qed. @@ -290,35 +272,33 @@ for @{ 'derivative ${default @{\lambda ${ident i} : $ty. $p)} @{\lambda ${ident i} . $p}}}. -interpretation "Rderivative" 'derivative \eta.f = - (cic:/matita/demo/power_derivative/derivative.con f). +interpretation "Rderivative" 'derivative \eta.f = (derivative f). *) -notation "hvbox(\frac 'd' ('d' 'x') break p)" with precedence 90 +notation "hvbox(\frac 'd' ('d' 'X') break p)" with precedence 90 for @{ 'derivative $p}. -interpretation "Rderivative" 'derivative f = - (cic:/matita/demo/power_derivative/derivative.con f). +interpretation "Rderivative" 'derivative f = (derivative f). -theorem derivative_power': ∀n:nat. D[x \sup (1+n)] = (1+n) · x \sup n. +theorem derivative_power': ∀n:nat. D[X \sup (1+n)] = (1+n) · X \sup n. assume n:nat. (*we proceed by induction on n to prove - (D[x \sup (1+n)] = (1+n) · x \sup n).*) elim n 0. + (D[X \sup (1+n)] = (1+n) · X \sup n).*) elim n 0. case O. - the thesis becomes (D[x \sup 1] = 1 · x \sup 0). + the thesis becomes (D[X \sup 1] = 1 · X \sup 0). done. case S (m:nat). by induction hypothesis we know - (D[x \sup (1+m)] = (1+m) · x \sup m) (H). + (D[X \sup (1+m)] = (1+m) · X \sup m) (H). the thesis becomes - (D[x \sup (2+m)] = (2+m) · x \sup (1+m)). + (D[X \sup (2+m)] = (2+m) · X \sup (1+m)). conclude - (D[x \sup (2+m)]) - = (D[x · x \sup (1+m)]). - = (D[x] · x \sup (1+m) + x · D[x \sup (1+m)]). - = (x \sup (1+m) + x · (costante (1+m) · x \sup m)). - = (x \sup (1+m) + costante (1+m) · x \sup (1+m)). - = ((2+m) · x \sup (1+m)) timeout=30 by Fmult_one_f, Fmult_commutative, + (D[X \sup (2+m)]) + = (D[X · X \sup (1+m)]). + = (D[X] · X \sup (1+m) + X · D[X \sup (1+m)]). + = (X \sup (1+m) + X · (costante (1+m) · X \sup m)). + = (X \sup (1+m) + costante (1+m) · X \sup (1+m)). + = ((2+m) · X \sup (1+m)) timeout=30 by Fmult_one_f, Fmult_commutative, Fmult_Fplus_distr, assoc_plus, plus_n_SO, costante_sum done. qed.