Source Latex
du cours de mathématiques
\documentclass[12pt]{article}
%\usepackage{french}
\usepackage{amsfonts}\usepackage{amssymb}
\usepackage[french]{babel}
\usepackage{amsmath}
\usepackage[latin1]{inputenc}
\usepackage{a4wide}
\usepackage{graphicx}
\usepackage{epsf}
\usepackage{calc}
\usepackage{enumerate}
\usepackage{array}
%\usepackage{pst-plot,pst-text,pst-tree}
%\usepackage{pst-all}
\usepackage{pst-func}
\usepackage{pstricks-add}
\usepackage{colortbl}
\usepackage{hyperref}
\hypersetup{
pdfauthor={Yoann Morel},
pdfsubject={Synth�se probabilit�s: variables al�atoires discr�tes
et continues},
pdftitle={Variables al�atoires discr�tes et continues},
pdfkeywords={Probabilit�s, Variables al�atoires discr�tes,
Variables al�atoires continues, v.a.,
discret, continu, discr�tes, continues,
loi de probabilit�, loi continue, densit� de probabilit�,
fonction de r�partition, loi binomiale, loi normale, gaussienne,
gauss, loi normale centr�e r�duite, loi exponentielle}
}
\hypersetup{
colorlinks = true,
linkcolor = red,
anchorcolor = red,
citecolor = blue,
filecolor = red,
pagecolor = red,
urlcolor = red
}
\voffset=-2.2cm
% Raccourcis diverses:
\newcommand{\nwc}{\newcommand}
\nwc{\dsp}{\displaystyle}
\nwc{\ct}{\centerline}
\nwc{\bge}{\begin{equation}}\nwc{\ene}{\end{equation}}
\nwc{\bgar}{\begin{array}}\nwc{\enar}{\end{array}}
\nwc{\bgit}{\begin{itemize}}\nwc{\enit}{\end{itemize}}
\nwc{\bgen}{\begin{enumerate}}\nwc{\enen}{\end{enumerate}}
\nwc{\la}{\left\{}\nwc{\ra}{\right\}}
\nwc{\lp}{\left(}\nwc{\rp}{\right)}
\nwc{\lb}{\left[}\nwc{\rb}{\right]}
\nwc{\bgsk}{\bigskip}
\nwc{\vsp}{\vspace{0.1cm}}
\nwc{\vspd}{\vspace{0.2cm}}
\nwc{\vspt}{\vspace{0.3cm}}
\nwc{\vspq}{\vspace{0.4cm}}
\def\N{{\rm I\kern-.1567em N}} % Doppel-N
\def\D{{\rm I\kern-.1567em D}} % Doppel-N
\def\No{\N_0} % Doppel-N unten 0
\def\R{{\rm I\kern-.1567em R}} % Doppel R
\def\C{{\rm C\kern-4.7pt % Doppel C
\vrule height 7.7pt width 0.4pt depth -0.5pt \phantom {.}}}
\def\Q{\mathbb{Q}}
\def\Z{{\sf Z\kern-4.5pt Z}} % Doppel Z
\def\euro{\mbox{\raisebox{.25ex}{{\it =}}\hspace{-.5em}{\sf C}}}
\renewcommand{\Re}{\mathcal{R}e}
\renewcommand{\Im}{\mathcal{I}\!m}
\def\epsi{\varepsilon}
\def\lbd{\lambda}
\def\tht{\theta}
\def\Cf{\mathcal{C}_f}
\nwc{\tm}{\times}
\nwc{\V}[1]{\overrightarrow{#1}}
\nwc{\zb}{\mbox{$0\hspace{-0.67em}\mid$}}
\nwc{\db}{\mbox{$\hspace{0.1em}|\hspace{-0.67em}\mid$}}
\nwc{\ul}[1]{\underline{#1}}
\newcounter{nex}%[section]
\setcounter{nex}{0}
\newenvironment{EX}{%
\stepcounter{nex}
\bgsk{\noindent {\bf Exercice }\arabic{nex}}\hspace{0.2cm}
}{}
\nwc{\bgex}{\begin{EX}}\nwc{\enex}{\end{EX}}
\nwc{\bgfg}{\begin{figure}}\nwc{\enfg}{\end{figure}}
\nwc{\epsx}{\epsfxsize}\nwc{\epsy}{\epsfysize}
\nwc{\bgmp}{\begin{minipage}}\nwc{\enmp}{\end{minipage}}
\nwc{\limcdt}[4]{
$\dsp
\lim_{\bgar{ll}\scriptstyle{#1}\vspace{-0.2cm}\\\scriptstyle{#2}\enar}
{#3}={#4}$
}
\nwc{\tq}{\ \mbox{\bf\Large /}\ }
\headheight=0.cm
\textheight=27.5cm
\topmargin=-1.8cm
\footskip=0.6cm
\textwidth=18.5cm
\oddsidemargin=-1.5cm
\parindent=0.2cm
\newlength{\ProgIndent}
\setlength{\ProgIndent}{0.3cm}
\setlength{\unitlength}{1cm}
\newcounter{ntheo}
\setcounter{ntheo}{1}
\newlength{\ltheo}
\nwc{\bgth}[1]{
\settowidth{\ltheo}{Th�or�me \arabic{ntheo}}
\noindent
\paragraph{Th�or�me}% \arabic{ntheo}}
\hspace{-0.5em}%\hspace{-0.4cm}
\bgmp[t]{\textwidth-\ltheo-0.5em}{\it #1}\enmp
\stepcounter{ntheo}
}
\newcounter{nprop}
\setcounter{nprop}{1}
\newlength{\lprop}
\nwc{\bgprop}[1]{
\settowidth{\lprop}{Propri�t� \arabic{nprop}}
\noindent
\paragraph{Propri�t�}% \arabic{ntheo}}
\hspace{-0.5em}%\hspace{-0.4cm}
\bgmp[t]{\textwidth-\lprop-0.5em}{\it #1}\enmp
\stepcounter{nprop}
}
\nwc{\bgcorol}[1]{
\settowidth{\ltheo}{Corollaire \arabic{ntheo}}
\noindent
\paragraph{Corollaire}% \arabic{ntheo}}
\hspace{-0.5em}%\hspace{-0.4cm}
\bgmp[t]{\textwidth-\ltheo-0.5em}{\it #1}\enmp
}
\newcounter{ndef}
\setcounter{ndef}{1}
\newlength{\ldef}
\nwc{\bgdef}[1]{
\settowidth{\ldef}{D�finition \arabic{ndef}}
\noindent
\paragraph{D�finition}% \arabic{ndef}}
\hspace{-0.5em}%\hspace{-0.4cm}
\bgmp[t]{\textwidth-\ldef-0.5em}{\it #1}\enmp
\stepcounter{ntheo}
}
\nwc{\bgproof}[1]{
\vspq\noindent
\ul{D�monstration:} #1
\hfill$\square$
}
% "Cadre" type Objectifs....
\nwc{\ObjTitle}{Objectif\!\!:\ \ }
\newlength{\lgObjTitle}
\newlength{\hgObj}
\newlength{\hgObjTitle}\settoheight{\hgObjTitle}{\ObjTitle}
\newcommand{\Obj}[1]{%
\begin{flushright}%
\settowidth{\lgObjTitle}{\ObjTitle}
\settototalheight{\hgObj}{\phantom{\bgmp{16.4cm}{\bf\emph{\ObjTitle}}#1\enmp}}
\bgmp{17.1cm}
\psline(-1ex,-\hgObj)(-1ex,-1.5\hgObjTitle)(\lgObjTitle,-1.5\hgObjTitle)\par
\bgmp{17.cm}{\bf\emph{\ObjTitle}}#1\enmp
\enmp
\end{flushright}
}
\renewcommand\thesection{\Roman{section}\ \ -}
\renewcommand\thesubsection{\arabic{subsection})}
\renewcommand\thesubsubsection{\hspace*{0.5cm}\alph{subsubsection})\hspace*{-0.4cm}}
% Bandeau en bas de page
\newcommand{\TITLE}{Variables al�atoires discr�tes et continues}
\author{Y. Morel}
\date{}
\usepackage{fancyhdr}
\pagestyle{fancyplain}
\setlength{\headheight}{0cm}
\renewcommand{\headrulewidth}{0pt}
\renewcommand{\footrulewidth}{0.5pt}
\lhead{}\chead{}\rhead{}
\lfoot{Y. Morel - \url{https://xymaths.fr}}
\rfoot{\thepage/\pageref{LastPage}}
\cfoot{\TITLE}
\title{\TITLE}
\pagestyle{fancy}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\begin{document}
\vspace*{-1.cm}
\ct{\LARGE{\bf \TITLE}}
\vspace{0.6cm}
\hspace{-0.5cm}%\noindent
\begin{tabular}{p{0.52\linewidth}|p{0.5\linewidth}}
Loi de probabilit� $P$ de la v.a. $X$
\[\begin{tabular}{*6{|c}|}\hline
$x_i$ & $x_1$ & $x_2$ & $x_3$& \dots & $x_n$ \\\hline
$\text{Prob}(X=x_i)$ & $p_1$ & $p_2$ & $p_3$ & \dots & $p_n$ \\\hline
\end{tabular}\]
&Densit� de probabilit� $f$ de la v.a. $X$ (d�finie sur $\R$)
\[\begin{tabular}{|c|ccc|}\hline
$x$ & $-\infty$ &\hspace*{1cm}& $+\infty$ \\\hline
&&&\\
$f(x)$&\psline{->}(0.2,-0.2)(1.,0.6)&\psline{->}(0.2,0.6)(1.,-0.2)&\\
&0&&0\\\hline
\end{tabular}\]
%\psline(-15,-0.5)(10,-0.5)
%\psline(-15,-1.5)(10,-1.5)
\\
\vspace{-0.4cm}
\bgit
\item[$\bullet$] pour tout $1\leqslant i\leqslant n$,\quad $p_i\geqslant 0$
\vsp
\item[$\bullet$] $\dsp\sum_{i=1}^n p_i=1$
\enit
&
\vspace{-0.4cm}
\bgit
\item[$\bullet$] pour tout $x\in\R$,\quad $f(x)\geqslant 0$
\vsp
\item[$\bullet$] $\dsp\int_{-\infty}^{+\infty} f(x)\,dx=1$
\enit
\\
\psset{arrowsize=5pt,unit=1cm}
\begin{pspicture}(-2,-0.)(7,4.6)
\psline{->}(-2,0)(7,0)\rput(7.3,-0.2){$x_i$}
\psline{->}(0,-0.2)(0,4.6)\rput(-1.1,4.4){$P(X=x_i)$}
%
\pspolygon(-1,0)(-0.5,0)(-0.5,0.5)(-1,0.5)\rput(-0.7,-0.25){$x_1$}
\pspolygon(-0.5,0)(-0.5,1.5)(0,1.5)(0,0)\rput(-0.2,-0.25){$x_2$}
\pspolygon(0,3)(0,0)(.5,0)(.5,3)\rput(.3,-0.25){$x_3$}
\pspolygon[fillstyle=solid,fillcolor=lightgray](.5,0)(.5,2.2)(1,2.2)(1,0)\rput(.8,-0.25){$x_4$}
\psline{->}(0.75,2.22)(1.7,4)
\rput(2.3,4.2){$p_4\!=\!P(X\!=\!x_4)$}
%
\rput(1.5,1.){$\dots$}
\rput(1.5,-0.25){$\dots$}
%
\pspolygon[fillstyle=vlines](2.,0)(2.,1.7)(2.5,1.7)(2.5,0)\rput(2.3,-0.25){$x_i$}
\pspolygon[fillstyle=vlines](2.5,0)(2.5,1.2)(3,1.2)(3,0)
%
\rput(3.5,1.){$\dots$}
\rput(3.5,-0.25){$\dots$}
%
\pspolygon[fillstyle=vlines](4,0)(4,1.4)(4.5,1.4)(4.5,0)\rput(4.3,-0.25){$x_j$}
%
\rput(5.2,1.){$\dots$}
\rput(5.2,-0.25){$\dots$}
%
\pspolygon(6,0)(6,0.4)(6.5,0.4)(6.5,0)\rput(6.3,-0.25){$x_n$}
%
\psbrace[ref=lt,rot=270,nodesepB=-2pt](4.5,2)(2,2){}
\rput(4.5,2.6){$P(x_i\leqslant X\leqslant x_j)=p_i+\dots+p_j$}
%\rput(-0.25,0.5){$p_1$}
%\rput(-0.25,1.5){$p_2$}\psline[linestyle=dotted](0,1.5)(0.5,1.5)
%\rput(-0.25,3){$p_3$}\psline[linestyle=dotted](0,3)(1,3)
%\rput(-0.25,2.2){$p_4$}\psline[linestyle=dotted](0,2.2)(1,2.2)
\end{pspicture}
&
\psset{arrowsize=5pt,unit=1cm}
\begin{pspicture}(-2.5,-0.)(6,4.6)
\psline{->}(-1.8,0)(6,0)\rput(6.3,-0.2){$x$}
\psline{->}(0,-0.2)(0,4.6)\rput(-0.3,4.6){$f$}
%
\nwc{\f}[1]{2.718 -1 #1 -1 add 2 exp mul exp 4.2 mul
2.718 -1 #1 -2.9 add 2 exp mul exp 2 mul
add}
\psplot[plotpoints=200]{-2}{5.8}{\f{x}}
%
\psline(1.5,0)(!1.5 \space \f{1.5})\rput(1.5,-0.25){$a$}
\psline(2,0)(!2 \space \f{2})\rput(2,-0.25){$b$}
\pscustom{
\psplot{1.5}{2}{\f{x}} \gsave
\psline(2,0)(1.5,0)
%\fill[fillstyle=solid, fillcolor=lightgray]
\fill[fillstyle=vlines]
\grestore }
\psline{->}(1.75,2.5)(2.2,3.8)
\rput(4,4){$\dsp P(a\leqslant X \leqslant b)\!=\!\int_a^b f(x)\,dx$}
%
\rput(0.4,-0.25){$\alpha$}
\psline(0.4,0)(!0.4 \space \f{0.4})
\psline{->}(! 0.3 \space \f{0.4})(-0.5,3.2)
\rput(-1.3,3.4){$P(X\!=\!\alpha)=0$}
\end{pspicture}
\\
\bgit
\item[$\bullet$] Esp�rance: $\dsp E(X)=\sum_{i=1}^n x_i\,p_i$
\vspd
\item[$\bullet$] Variance:
$\bgar[t]{ll}
V(X)
&\dsp=E\Bigr((X-E(X)^2\Bigl)\\
&\dsp=\sum_{k=1}^n \lp x-E(X)\rp^2\,p_i
\enar$
\vspd
\item[$\bullet$] Ecart type: $\sigma=\sqrt{V(X)}$
\enit
&
\bgit
\item[$\bullet$] Esp�rance: $\dsp E(X)=\int_{-\infty}^{+\infty} x\,f(x)\,dx$
\vspd
\item[$\bullet$] Variance:
$\bgar[t]{ll}
V(X)
&\dsp=E\Bigr((X-E(X)^2\Bigl)\\
&\dsp=\int_{-\infty}^{+\infty} \lp x-E(X)\rp^2\,f(x)\,dx
\enar$
\vspd
\item[$\bullet$] Ecart type: $\sigma=\sqrt{V(X)}$
\enit
\\
\noindent
\ul{Probabilit�s cumul�es croissantes}
\[P(X\!\leqslant\! x_i)=\sum_{k=1}^i p_k\]
\[\begin{tabular}{*7{|c}|}\hline
\multicolumn{2}{|c|}{$x_i$} & $x_1$ & $x_2$ & $x_3$& \dots & $x_n$ \\\hline
\multicolumn{2}{|c|}{$P(X=x_i)$} & $p_1$ & $p_2$ & $p_3$ & \dots &$p_n$
\\\hline
$P(X\leqslant x_i)$&$0$ & $p_1$ & $p_1\!+\!p_2$ &
$p_1\!+\!p_2\!+\!p_3$ & $\dots$ & $1$\\\hline
\end{tabular}
\]
&
\ul{Fonction de r�partition}
$\bgar[t]{ll}
F(x)&=P(X\!\leqslant\! x)\\[0.2cm]
&\dsp=\int_{-\infty}^x f(t)\,dt
\enar$
\vspd
\[\begin{tabular}{|c|ccc|}\hline
$x$ & $-\infty$ &\hspace*{1cm}& $+\infty$ \\\hline
&&&\\
$f(x)$&\psline{->}(0.2,-0.2)(1.,0.6)&\psline{->}(0.2,0.6)(1.,-0.2)&\\
&0&&0\\\hline
&&&$1$\\
$F(x)$ &\psline{->}(0.2,-0.2)(2.2,0.6)&&\\
&$0$ && \\\hline
\end{tabular}
\]
\\
\ul{Loi binomiale $\mathcal{B}(n,p)$} \quad
$E(X)=np$, $\sigma(X)=\sqrt{npq}$
%\vsp
&\ul{Loi normale $\mathcal{N}(m,\sigma)$}\quad
$E(X)=m$, $\sigma(X)=\sigma$
%\vsp
\\
$\dsp P(X=k)=C_n^k p^k (1-p)^{n-k}$
&
$\dsp f(x)
=\dfrac{1}{\sigma\sqrt{2\pi}}e^{-\frac{(x-m)^2}{2\sigma^2}}$, \quad
$P(X=a)=0$
\\
$\dsp
P(X\leqslant N)
=\sum_{k=1}^N P(X=k)
=\sum_{k=1}^N C_n^k p^k (1-p)^{n-k}$
&$\dsp P(X\leqslant a)=\int_{-\infty}^a f(x)\,dx=\Pi(a)$
\\
$\dsp
P(N_1\leqslant X\leqslant N_2)
=\sum_{k=N_1}^{N_2} C_n^k p^k (1-p)^{n-k}$
&
$\dsp P(a<X\leqslant b)=\int_{a}^b f(x)\,dx=\Pi(b)-\Pi(a)$
\\
\end{tabular}
\label{LastPage}
\end{document}
Télécharger le fichier source