diff --git "a/Chapitre 1 - Systemes equations lineaires/1.1. Introduction et d\303\251finition.ipynb" "b/Chapitre 1 - Systemes equations lineaires/1.1. Introduction et d\303\251finition.ipynb" index 2c9d3a6..258dc83 100644 --- "a/Chapitre 1 - Systemes equations lineaires/1.1. Introduction et d\303\251finition.ipynb" +++ "b/Chapitre 1 - Systemes equations lineaires/1.1. Introduction et d\303\251finition.ipynb" @@ -1,311 +1,302 @@ { "cells": [ { "cell_type": "markdown", "metadata": {}, "source": [ "# Concept(s)-clé(s) et théorie\n", "\n", "### DÉFINITION 1 :\n", "\n", "Une *équation linéaire* aux inconnues $x_1,\\ldots,x_n$ à coefficients réels est une équation de la forme\n", "\n", "$$a_1x_1+a_2x_2+\\cdots+a_nx_n=b,$$ \n", "où $a_1,a_2,\\ldots,a_n,b\\in \\mathbb{R}.$\n", " \n", "---\n", "### DÉFINITION 2 :\n", "\n", "On appelle *système d'équations linéaires* (ou simplement système linéaire) une famille d'équations linéaires aux inconnues $x_1,\\ldots,x_n$ à coefficients réels de la forme \n", "\n", "$$S=\\left\\{\\begin{array}{ccccccc}\n", "a_{11}x_1 &+a_{12}x_2 & + &\\cdots &+a_{1n}x_n &= &b_1 \\\\\n", "a_{21}x_1 &+a_{22}x_2 & + &\\cdots &+a_{2n}x_n &= &b_2 \\\\\n", "\\vdots & & & &\\vdots & \\vdots &\\vdots \\\\\n", "a_{m1}x_1 &+a_{m2}x_2 & + &\\cdots &+a_{mn}x_n &= &b_m\n", "\\end{array},\\right. $$\n", "\n", "où $a_{ij},b_i\\in \\mathbb{R}$ pour tout $1\\leq i\\leq m$ et tout $1\\leq j\\leq n.$ \n", "\n", "Aussi, on dit qu'une suite ordonnée de $n$ nombres réels $\\alpha=(\\alpha_1,\\ldots,\\alpha_n)$ est une *solution du système linéaire* $S$ si toutes les égalités du système sont vérifiées lorsque l'on remplace $x_j$ par $\\alpha_j,$ ceci pout tout $1\\leq j\\leq n.$" ] }, { "cell_type": "code", "execution_count": null, "metadata": {}, "outputs": [], "source": [ "import Librairie.AL_Fct as al\n", "#from IPython.core.magic import register_cell_magic\n", "#from IPython.display import HTML, display\n", "#import numpy as np" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "### EXEMPLE 1\n", "\n", "Dans ce premier exemple nous nous familiarisons avec les équations et les ensembles de solutions. Soit \n", "$$ \n", "a_{1}x_{1} + a_{2}x_{2} + \\ldots a_{n}x_{n}=b_1.\n", "$$ \n", "On utilise *la syntaxe suivante pour définir les coefficients* de l'équation \n", "\n", "$$\n", "\\begin{align*}\n", "A&=[a_1, a_2, \\ldots, a_n]\\\\\n", "b&=[b_1].\n", "\\end{align*}\n", "$$\n", "\n", "---\n", "Dans la case ci-dessous, entrer les coefficients de l'équation \n", "$$3x_1 + 2x_2=7$$\n", "\n" ] }, { "cell_type": "code", "execution_count": null, "metadata": {}, "outputs": [], "source": [ "al.bgc('seashell')\n", "#Toutes les valeurs sont initialisées à 1\n", "\n", "A = [1] \n", "b = [1]\n" ] }, { "cell_type": "code", "execution_count": null, "metadata": {}, "outputs": [], "source": [ "al.printEq(A,b)" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "On utilise *la syntaxe suivante pour entrer une solution* d'une équation\n", "$$\\rm{alpha}=[\\alpha_1, \\alpha_2, \\ldots, \\alpha_n]$$" ] }, { "cell_type": "code", "execution_count": null, "metadata": {}, "outputs": [], "source": [ "al.bgc('seashell')\n", "#Toutes les valeurs sont initialisées à 1\n", "\n", - "alpha = [1] #solution" + "alpha = [1, 1] #solution" ] }, { "cell_type": "code", "execution_count": null, "metadata": {}, "outputs": [], "source": [ - "isSol = [al.SolOfEq(alpha, A+b,1)]" + "isSol = [al.SolOfEq(alpha, A+b, 1)]" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "### **EXERCICE 1**\n", "\n", "Enter l'équation $$ \\frac{2}{5}x_1 -4x_2 + x_3 = 8$$ et donner une solution $$\\alpha=(\\alpha_1, \\alpha_2, \\alpha_3).$$\n", "\n", "Vous pouvez aussi adapter le code à l'équation de votre choix." ] }, { "cell_type": "code", "execution_count": null, "metadata": {}, "outputs": [], "source": [ "al.bgc('seashell')\n", "\n", "#Par défaut, les valeurs sont fixées à 1\n", "\n", "A = [1] \n", "b =[1]\n", "alpha = [1] #solution " ] }, { "cell_type": "code", "execution_count": null, "metadata": {}, "outputs": [], "source": [ "al.printEq(A,b)\n", "isSol=[al.SolOfEq(alpha, A+b,1)]" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "### EXEMPLE 2\n", "\n", "Dans cet exercice nous nous familiarisonns avec les systèmes d'équations. La partie ci-dessous vous demande de rentrer un système d'équation. \n", "\n", "Soit\n", "$$S=\\left\\{\\begin{array}{ccccccc}\n", "a_{11}x_1 &+a_{12}x_2 & + &\\cdots &+a_{1n}x_n &= &b_1 \\\\\n", "a_{21}x_1 &+a_{22}x_2 & + &\\cdots &+a_{2n}x_n &= &b_2 \\\\\n", "\\vdots & & & &\\vdots & \\vdots &\\vdots \\\\\n", "a_{m1}x_1 &+a_{m2}x_2 & + &\\cdots &+a_{mn}x_n &= &b_m\n", "\\end{array},\\right. $$\n", "\n", "On utilise *la syntaxe suivante pour entrer les coefficients du système*\n", "\n", "$$\n", "\\begin{align*}\n", "A&=\\quad [\\quad [ a_{11} , a_{12}, \\ldots, a_{1n} ], \\quad [ a_{21}, a_{22}, \\ldots, a_{2n}]\\quad, \\ldots , \\quad[a_{m1}, a_{m2}, \\ldots, a_{mn}]\\quad]\\\\\n", "b&=\\quad [\\quad b_1, b_2, \\ldots, b_m \\quad]\n", "\\end{align*}$$\n", "\n", "---\n", "Essayer d'entrer le système d'équations ci-dessous\n", "\n", "$$\\begin{cases}\n", - "x_1 &-3 x_2 &&=4\\\\\n", - "-x_1 & + 4 x_2&&= 5\n", + "x_1 &- & 3 x_2 && = 4\\\\\n", + "-x_1 & + & 4 x_2 && = 5\n", "\\end{cases}\n", "$$" ] }, { "cell_type": "code", "execution_count": null, "metadata": {}, "outputs": [], "source": [ "al.bgc('seashell')\n", "\n", "#Par défaut, les valeurs sont fixées à 1\n", "\n", "A = [ [1, 1], [1, 1]] \n", - "b=[1,1] \n", - "alpha = [1,1] #solution" + "b=[1, 1] \n", + "alpha = [1, 1] #solution" ] }, { "cell_type": "code", "execution_count": null, "metadata": {}, "outputs": [], "source": [ "al.printSyst(A,b)" ] }, { "cell_type": "code", "execution_count": null, "metadata": {}, "outputs": [], "source": [ "al.SolOfSyst(alpha, A,b)" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "### **EXERCICE 2**\n", " \n", "Entrer le système suivant et donner une solution du système.\n", "\n", "$$\\begin{cases}\n", "&2x_1 -3 x_2 + x_3&&=-5\\\\\n", "&-\\dfrac{1}{3}x_1 + x_3&&= 2\\\\\n", "&x_1 + 4x_2 -x_3 &&=0\n", "\\end{cases}\n", "$$\n", "\n", "Vous pouvez aussi adapter le code à l'équation de votre choix." ] }, { "cell_type": "code", "execution_count": null, "metadata": {}, "outputs": [], "source": [ "al.bgc('seashell')\n", "#Par défaut, les valeurs sont fixées à 1\n", "\n", "A = [[1,1,1], [1,1,1], [1,1,1]]\n", "b =[1,1,1]\n", "alpha =[1,1,1] #solution\n" ] }, { "cell_type": "code", "execution_count": null, "metadata": {}, "outputs": [], "source": [ "al.printSyst(A,b)\n", "al.SolOfSyst(alpha, A,b)" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "[Passez au notebook du chapitre 1.2: Nombre de solutions d'un système](./1.2.%20Nombre%20de%20solution%20d'un%20système.ipynb)" ] }, - { - "cell_type": "code", - "execution_count": null, - "metadata": {}, - "outputs": [], - "source": [ - "b=al.np.array([1,2,3])" - ] - }, { "cell_type": "code", "execution_count": null, "metadata": {}, "outputs": [], "source": [] } ], "metadata": { "kernelspec": { "display_name": "Python 3", "language": "python", "name": "python3" }, "language_info": { "codemirror_mode": { "name": "ipython", "version": 3 }, "file_extension": ".py", "mimetype": "text/x-python", "name": "python", "nbconvert_exporter": "python", "pygments_lexer": "ipython3", - "version": "3.6.8" + "version": "3.7.4" } }, "nbformat": 4, "nbformat_minor": 4 }