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-rwxr-xr-xuni_notes/algebra.html352
1 files changed, 176 insertions, 176 deletions
diff --git a/uni_notes/algebra.html b/uni_notes/algebra.html
index 27c8d76..9323119 100755
--- a/uni_notes/algebra.html
+++ b/uni_notes/algebra.html
@@ -3,7 +3,7 @@
 "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
 <html xmlns="http://www.w3.org/1999/xhtml" lang="en" xml:lang="en">
 <head>
-<!-- 2023-10-11 Wed 19:04 -->
+<!-- 2023-10-13 Fri 16:58 -->
 <meta http-equiv="Content-Type" content="text/html;charset=utf-8" />
 <meta name="viewport" content="width=device-width, initial-scale=1" />
 <title>Algebra 1</title>
@@ -47,13 +47,13 @@
 <body>
 <div id="content" class="content">
 <h1 class="title">Algebra 1</h1>
-<div id="outline-container-orgcc5f4d8" class="outline-2">
-<h2 id="orgcc5f4d8">Contenu de la Matiére</h2>
-<div class="outline-text-2" id="text-orgcc5f4d8">
+<div id="outline-container-orgc134a5b" class="outline-2">
+<h2 id="orgc134a5b">Contenu de la Matiére</h2>
+<div class="outline-text-2" id="text-orgc134a5b">
 </div>
-<div id="outline-container-orgf4040f2" class="outline-3">
-<h3 id="orgf4040f2">Rappels et compléments (11H)</h3>
-<div class="outline-text-3" id="text-orgf4040f2">
+<div id="outline-container-orgae00938" class="outline-3">
+<h3 id="orgae00938">Rappels et compléments (11H)</h3>
+<div class="outline-text-3" id="text-orgae00938">
 <ul class="org-ul">
 <li>Logique mathématique et méthodes du raisonnement mathématique</li>
 <li>Ensembles et Relations</li>
@@ -61,9 +61,9 @@
 </ul>
 </div>
 </div>
-<div id="outline-container-orge74cdc9" class="outline-3">
-<h3 id="orge74cdc9">Structures Algébriques (11H)</h3>
-<div class="outline-text-3" id="text-orge74cdc9">
+<div id="outline-container-org0eb35c9" class="outline-3">
+<h3 id="org0eb35c9">Structures Algébriques (11H)</h3>
+<div class="outline-text-3" id="text-org0eb35c9">
 <ul class="org-ul">
 <li>Groupes et morphisme de groupes</li>
 <li>Anneaux et morphisme d&rsquo;anneaux</li>
@@ -71,9 +71,9 @@
 </ul>
 </div>
 </div>
-<div id="outline-container-org0b54650" class="outline-3">
-<h3 id="org0b54650">Polynômes et fractions rationnelles</h3>
-<div class="outline-text-3" id="text-org0b54650">
+<div id="outline-container-org4a088f6" class="outline-3">
+<h3 id="org4a088f6">Polynômes et fractions rationnelles</h3>
+<div class="outline-text-3" id="text-org4a088f6">
 <ul class="org-ul">
 <li>Notion du polynôme à une indéterminée á coefficients dans un anneau</li>
 <li>Opérations Algébriques sur les polynômes</li>
@@ -86,9 +86,9 @@
 </div>
 </div>
 </div>
-<div id="outline-container-org9dbc8bb" class="outline-2">
-<h2 id="org9dbc8bb">Premier cours : Logique mathématique et méthodes du raisonnement mathématique <i>Sep 25</i> :</h2>
-<div class="outline-text-2" id="text-org9dbc8bb">
+<div id="outline-container-org73264c6" class="outline-2">
+<h2 id="org73264c6">Premier cours : Logique mathématique et méthodes du raisonnement mathématique <i>Sep 25</i> :</h2>
+<div class="outline-text-2" id="text-org73264c6">
 <p>
 Let <b>P</b> <b>Q</b> and <b>R</b> be propositions which can either be <b>True</b> or <b>False</b>. And let&rsquo;s also give the value <b>1</b> to each <b>True</b> proposition and <b>0</b> to each false one.
 </p>
@@ -438,13 +438,13 @@ A proposition is equivalent to another only when both of them have <b>the same v
 <i>Note: P implying Q is equivalent to P̅ implying Q̅, or: (P ⇒ Q) ⇔ (P̅ ⇒ Q̅)</i>
 </p>
 </div>
-<div id="outline-container-org29099d5" class="outline-3">
-<h3 id="org29099d5">Properties:</h3>
-<div class="outline-text-3" id="text-org29099d5">
+<div id="outline-container-org74d9557" class="outline-3">
+<h3 id="org74d9557">Properties:</h3>
+<div class="outline-text-3" id="text-org74d9557">
 </div>
-<div id="outline-container-orgfeb62c8" class="outline-4">
-<h4 id="orgfeb62c8"><b>Absorption</b>:</h4>
-<div class="outline-text-4" id="text-orgfeb62c8">
+<div id="outline-container-orgc7f1d03" class="outline-4">
+<h4 id="orgc7f1d03"><b>Absorption</b>:</h4>
+<div class="outline-text-4" id="text-orgc7f1d03">
 <p>
 (P ∨ P) ⇔ P
 </p>
@@ -454,9 +454,9 @@ A proposition is equivalent to another only when both of them have <b>the same v
 </p>
 </div>
 </div>
-<div id="outline-container-org2fa2b1f" class="outline-4">
-<h4 id="org2fa2b1f"><b>Commutativity</b>:</h4>
-<div class="outline-text-4" id="text-org2fa2b1f">
+<div id="outline-container-orgcb729de" class="outline-4">
+<h4 id="orgcb729de"><b>Commutativity</b>:</h4>
+<div class="outline-text-4" id="text-orgcb729de">
 <p>
 (P ∧ Q) ⇔ (Q ∧ P)
 </p>
@@ -466,9 +466,9 @@ A proposition is equivalent to another only when both of them have <b>the same v
 </p>
 </div>
 </div>
-<div id="outline-container-orge30be26" class="outline-4">
-<h4 id="orge30be26"><b>Associativity</b>:</h4>
-<div class="outline-text-4" id="text-orge30be26">
+<div id="outline-container-org4ae8933" class="outline-4">
+<h4 id="org4ae8933"><b>Associativity</b>:</h4>
+<div class="outline-text-4" id="text-org4ae8933">
 <p>
 P ∧ (Q ∧ R) ⇔ (P ∧ Q) ∧ R
 </p>
@@ -478,9 +478,9 @@ P ∨ (Q ∨ R) ⇔ (P ∨ Q) ∨ R
 </p>
 </div>
 </div>
-<div id="outline-container-orgd1de8d5" class="outline-4">
-<h4 id="orgd1de8d5"><b>Distributivity</b>:</h4>
-<div class="outline-text-4" id="text-orgd1de8d5">
+<div id="outline-container-org095f4a6" class="outline-4">
+<h4 id="org095f4a6"><b>Distributivity</b>:</h4>
+<div class="outline-text-4" id="text-org095f4a6">
 <p>
 P ∧ (Q ∨ R) ⇔ (P ∧ Q) ∨ (P ∧ R)
 </p>
@@ -490,9 +490,9 @@ P ∨ (Q ∧ R) ⇔ (P ∨ Q) ∧ (P ∨ R)
 </p>
 </div>
 </div>
-<div id="outline-container-org8c5c9f6" class="outline-4">
-<h4 id="org8c5c9f6"><b>Neutral element</b>:</h4>
-<div class="outline-text-4" id="text-org8c5c9f6">
+<div id="outline-container-orgf7e29ee" class="outline-4">
+<h4 id="orgf7e29ee"><b>Neutral element</b>:</h4>
+<div class="outline-text-4" id="text-orgf7e29ee">
 <p>
 <i>We define proposition <b>T</b> to be always <b>true</b> and <b>F</b> to be always <b>false</b></i>
 </p>
@@ -506,9 +506,9 @@ P ∨ F ⇔ P
 </p>
 </div>
 </div>
-<div id="outline-container-orgf102dde" class="outline-4">
-<h4 id="orgf102dde"><b>Negation of a conjunction &amp; a disjunction</b>:</h4>
-<div class="outline-text-4" id="text-orgf102dde">
+<div id="outline-container-org9bfee59" class="outline-4">
+<h4 id="org9bfee59"><b>Negation of a conjunction &amp; a disjunction</b>:</h4>
+<div class="outline-text-4" id="text-org9bfee59">
 <p>
 Now we won&rsquo;t use bars here because my lazy ass doesn&rsquo;t know how, so instead I will use not()!!!
 </p>
@@ -526,25 +526,25 @@ not(<b>P ∨ Q</b>) ⇔ P̅ ∧ Q̅
 </p>
 </div>
 </div>
-<div id="outline-container-org9534ece" class="outline-4">
-<h4 id="org9534ece"><b>Transitivity</b>:</h4>
-<div class="outline-text-4" id="text-org9534ece">
+<div id="outline-container-orgd144fb3" class="outline-4">
+<h4 id="orgd144fb3"><b>Transitivity</b>:</h4>
+<div class="outline-text-4" id="text-orgd144fb3">
 <p>
-[(P ⇒ Q) (Q ⇒ R)] ⇔ P ⇒ R
+[(P ⇒ Q) AND (Q ⇒ R)] ⇔ P ⇒ R
 </p>
 </div>
 </div>
-<div id="outline-container-org90fa987" class="outline-4">
-<h4 id="org90fa987"><b>Contraposition</b>:</h4>
-<div class="outline-text-4" id="text-org90fa987">
+<div id="outline-container-orgbc26f01" class="outline-4">
+<h4 id="orgbc26f01"><b>Contraposition</b>:</h4>
+<div class="outline-text-4" id="text-orgbc26f01">
 <p>
 (P ⇒ Q) ⇔ (Q̅ ⇒ P̅)
 </p>
 </div>
 </div>
-<div id="outline-container-orga2d0ece" class="outline-4">
-<h4 id="orga2d0ece">God only knows what this property is called:</h4>
-<div class="outline-text-4" id="text-orga2d0ece">
+<div id="outline-container-org70fd37a" class="outline-4">
+<h4 id="org70fd37a">God only knows what this property is called:</h4>
+<div class="outline-text-4" id="text-org70fd37a">
 <p>
 <i>If</i>
 </p>
@@ -558,7 +558,7 @@ and
 </p>
 
 <p>
-(Q̅ ⇒ Q) is true
+(P̅ ⇒ Q) is true
 </p>
 
 <p>
@@ -571,17 +571,17 @@ Q is always true
 </div>
 </div>
 </div>
-<div id="outline-container-org35a43b7" class="outline-3">
-<h3 id="org35a43b7">Some exercices I found online :</h3>
-<div class="outline-text-3" id="text-org35a43b7">
+<div id="outline-container-org6dd9c74" class="outline-3">
+<h3 id="org6dd9c74">Some exercices I found online :</h3>
+<div class="outline-text-3" id="text-org6dd9c74">
 </div>
-<div id="outline-container-orgf619324" class="outline-4">
-<h4 id="orgf619324">USTHB 2022/2023 Section B :</h4>
-<div class="outline-text-4" id="text-orgf619324">
+<div id="outline-container-org5a46794" class="outline-4">
+<h4 id="org5a46794">USTHB 2022/2023 Section B :</h4>
+<div class="outline-text-4" id="text-org5a46794">
 </div>
 <ul class="org-ul">
-<li><a id="org1c47389"></a>Exercice 1: Démontrer les équivalences suivantes:<br />
-<div class="outline-text-5" id="text-org1c47389">
+<li><a id="orgdcdfa08"></a>Exercice 1: Démontrer les équivalences suivantes:<br />
+<div class="outline-text-5" id="text-orgdcdfa08">
 <ol class="org-ol">
 <li><p>
 (P ⇒ Q) ⇔ (Q̅ ⇒ P̅)
@@ -635,8 +635,8 @@ Literally the same as above 🩷
 </ol>
 </div>
 </li>
-<li><a id="org688fdcc"></a>Exercice 2: Dire si les propositions suivantes sont vraies ou fausses, et les nier:<br />
-<div class="outline-text-5" id="text-org688fdcc">
+<li><a id="orgfc2dd28"></a>Exercice 2: Dire si les propositions suivantes sont vraies ou fausses, et les nier:<br />
+<div class="outline-text-5" id="text-orgfc2dd28">
 <ol class="org-ol">
 <li><p>
 ∀x ∈ ℝ ,∃y ∈ ℝ*+, tels que e^x = y
@@ -769,13 +769,13 @@ y + x &lt; 8
 </div>
 </div>
 </div>
-<div id="outline-container-orgac834f2" class="outline-2">
-<h2 id="orgac834f2">2éme cours <i>Oct 2</i></h2>
-<div class="outline-text-2" id="text-orgac834f2">
+<div id="outline-container-org8e69635" class="outline-2">
+<h2 id="org8e69635">2éme cours <i>Oct 2</i></h2>
+<div class="outline-text-2" id="text-org8e69635">
 </div>
-<div id="outline-container-org42a8fad" class="outline-3">
-<h3 id="org42a8fad">Quantifiers</h3>
-<div class="outline-text-3" id="text-org42a8fad">
+<div id="outline-container-org1d4ffa3" class="outline-3">
+<h3 id="org1d4ffa3">Quantifiers</h3>
+<div class="outline-text-3" id="text-org1d4ffa3">
 <p>
 A propriety P can depend on a parameter x
 </p>
@@ -791,8 +791,8 @@ A propriety P can depend on a parameter x
 </p>
 </div>
 <ul class="org-ul">
-<li><a id="org48c4773"></a>Example<br />
-<div class="outline-text-6" id="text-org48c4773">
+<li><a id="orgd0b7f53"></a>Example<br />
+<div class="outline-text-6" id="text-orgd0b7f53">
 <p>
 P(x) : x+1≥0
 </p>
@@ -803,13 +803,13 @@ P(X) is True or False depending on the values of x
 </div>
 </li>
 </ul>
-<div id="outline-container-org923b5fe" class="outline-4">
-<h4 id="org923b5fe">Proprieties</h4>
-<div class="outline-text-4" id="text-org923b5fe">
+<div id="outline-container-orga7cd185" class="outline-4">
+<h4 id="orga7cd185">Proprieties</h4>
+<div class="outline-text-4" id="text-orga7cd185">
 </div>
 <ul class="org-ul">
-<li><a id="orgaf93dd2"></a>Propriety Number 1:<br />
-<div class="outline-text-5" id="text-orgaf93dd2">
+<li><a id="org7460082"></a>Propriety Number 1:<br />
+<div class="outline-text-5" id="text-org7460082">
 <p>
 The negation of the universal quantifier is the existential quantifier, and vice-versa :
 </p>
@@ -820,8 +820,8 @@ The negation of the universal quantifier is the existential quantifier, and vice
 </ul>
 </div>
 <ul class="org-ul">
-<li><a id="orgf4f038f"></a>Example:<br />
-<div class="outline-text-6" id="text-orgf4f038f">
+<li><a id="org27b8375"></a>Example:<br />
+<div class="outline-text-6" id="text-org27b8375">
 <p>
 ∀ x ≥ 1  x² &gt; 5 ⇔ ∃ x ≥ 1 x² &lt; 5
 </p>
@@ -829,8 +829,8 @@ The negation of the universal quantifier is the existential quantifier, and vice
 </li>
 </ul>
 </li>
-<li><a id="org2c00dae"></a>Propriety Number 2:<br />
-<div class="outline-text-5" id="text-org2c00dae">
+<li><a id="org21aa647"></a>Propriety Number 2:<br />
+<div class="outline-text-5" id="text-org21aa647">
 <p>
 <b>∀x ∈ E, [P(x) ∧ Q(x)] ⇔ [∀ x ∈ E, P(x)] ∧ [∀ x ∈ E, Q(x)]</b>
 </p>
@@ -841,8 +841,8 @@ The propriety &ldquo;For any value of x from a set E , P(x) and Q(x)&rdquo; is e
 </p>
 </div>
 <ul class="org-ul">
-<li><a id="orga95ad05"></a>Example :<br />
-<div class="outline-text-6" id="text-orga95ad05">
+<li><a id="orgb4e2845"></a>Example :<br />
+<div class="outline-text-6" id="text-orgb4e2845">
 <p>
 P(x) : sqrt(x) &gt; 0 ;  Q(x) : x ≥ 1
 </p>
@@ -860,8 +860,8 @@ P(x) : sqrt(x) &gt; 0 ;  Q(x) : x ≥ 1
 </li>
 </ul>
 </li>
-<li><a id="orgfe5ddf2"></a>Propriety Number 3:<br />
-<div class="outline-text-5" id="text-orgfe5ddf2">
+<li><a id="orgce6dd51"></a>Propriety Number 3:<br />
+<div class="outline-text-5" id="text-orgce6dd51">
 <p>
 <b>∃ x ∈ E, [P(x) ∧ Q(x)] <i>⇒</i> [∃ x ∈ E, P(x)] ∧ [∃ x ∈ E, Q(x)]</b>
 </p>
@@ -872,8 +872,8 @@ P(x) : sqrt(x) &gt; 0 ;  Q(x) : x ≥ 1
 </p>
 </div>
 <ul class="org-ul">
-<li><a id="orgca7bea7"></a>Example of why it&rsquo;s NOT an equivalence :<br />
-<div class="outline-text-6" id="text-orgca7bea7">
+<li><a id="org956d29b"></a>Example of why it&rsquo;s NOT an equivalence :<br />
+<div class="outline-text-6" id="text-org956d29b">
 <p>
 P(x) : x &gt; 5  ;  Q(x) : x &lt; 5
 </p>
@@ -886,8 +886,8 @@ Of course there is no value of x such as its inferior and superior to 5 at the s
 </li>
 </ul>
 </li>
-<li><a id="orgf4ecdc0"></a>Propriety Number 4:<br />
-<div class="outline-text-5" id="text-orgf4ecdc0">
+<li><a id="orgce400d9"></a>Propriety Number 4:<br />
+<div class="outline-text-5" id="text-orgce400d9">
 <p>
 <b>[∀ x ∈ E, P(x)] ∨ [∀ x ∈ E, Q(x)] <i>⇒</i> ∀x ∈ E, [P(x) ∨ Q(x)]</b>
 </p>
@@ -901,16 +901,16 @@ Of course there is no value of x such as its inferior and superior to 5 at the s
 </ul>
 </div>
 </div>
-<div id="outline-container-org6421557" class="outline-3">
-<h3 id="org6421557">Multi-parameter proprieties :</h3>
-<div class="outline-text-3" id="text-org6421557">
+<div id="outline-container-org48fa1b7" class="outline-3">
+<h3 id="org48fa1b7">Multi-parameter proprieties :</h3>
+<div class="outline-text-3" id="text-org48fa1b7">
 <p>
 A propriety P can depend on two or more parameters, for convenience we call them x,y,z&#x2026;etc
 </p>
 </div>
 <ul class="org-ul">
-<li><a id="org314cff3"></a>Example :<br />
-<div class="outline-text-6" id="text-org314cff3">
+<li><a id="org985d3f3"></a>Example :<br />
+<div class="outline-text-6" id="text-org985d3f3">
 <p>
 P(x,y): x+y &gt; 0
 </p>
@@ -926,8 +926,8 @@ P(-2,-1) is a False one
 </p>
 </div>
 </li>
-<li><a id="orga9b6089"></a>WARNING :<br />
-<div class="outline-text-6" id="text-orga9b6089">
+<li><a id="orgd3167fe"></a>WARNING :<br />
+<div class="outline-text-6" id="text-orgd3167fe">
 <p>
 ∀x ∈ E, ∃y ∈ F , P(x,y)
 </p>
@@ -943,8 +943,8 @@ Are different because in the first one y depends on x, while in the second one,
 </p>
 </div>
 <ul class="org-ul">
-<li><a id="org3c5e5a8"></a>Example :<br />
-<div class="outline-text-7" id="text-org3c5e5a8">
+<li><a id="orge81043c"></a>Example :<br />
+<div class="outline-text-7" id="text-orge81043c">
 <p>
 ∀ x ∈ ℕ , ∃ y ∈ ℕ y &gt; x -&#x2013;&#x2014; True
 </p>
@@ -958,8 +958,8 @@ Are different because in the first one y depends on x, while in the second one,
 </ul>
 </li>
 </ul>
-<li><a id="org2f3208e"></a>Proprieties :<br />
-<div class="outline-text-5" id="text-org2f3208e">
+<li><a id="org96c2514"></a>Proprieties :<br />
+<div class="outline-text-5" id="text-org96c2514">
 <ol class="org-ol">
 <li>not(∀x ∈ E ,∃y ∈ F P(x,y)) ⇔ ∃x ∈ E, ∀y ∈ F not(P(x,y))</li>
 <li>not(∃x ∈ E ,∀y ∈ F P(x,y)) ⇔ ∀x ∈ E, ∃y ∈ F not(P(x,y))</li>
@@ -968,20 +968,20 @@ Are different because in the first one y depends on x, while in the second one,
 </li>
 </ul>
 </div>
-<div id="outline-container-orgc25dd7a" class="outline-3">
-<h3 id="orgc25dd7a">Methods of mathematical reasoning :</h3>
-<div class="outline-text-3" id="text-orgc25dd7a">
+<div id="outline-container-org47ee190" class="outline-3">
+<h3 id="org47ee190">Methods of mathematical reasoning :</h3>
+<div class="outline-text-3" id="text-org47ee190">
 </div>
-<div id="outline-container-orgf843851" class="outline-4">
-<h4 id="orgf843851">Direct reasoning :</h4>
-<div class="outline-text-4" id="text-orgf843851">
+<div id="outline-container-org24c7fa4" class="outline-4">
+<h4 id="org24c7fa4">Direct reasoning :</h4>
+<div class="outline-text-4" id="text-org24c7fa4">
 <p>
 To show that an implication P ⇒ Q is true, we suppose that P is true and we show that Q is true
 </p>
 </div>
 <ul class="org-ul">
-<li><a id="org6dd2136"></a>Example:<br />
-<div class="outline-text-5" id="text-org6dd2136">
+<li><a id="orgfa904f5"></a>Example:<br />
+<div class="outline-text-5" id="text-orgfa904f5">
 <p>
 Let a,b be two Real numbers, we have to prove that <b>a² + b² = 1 ⇒ |a + b| ≤ 2</b>
 </p>
@@ -1024,9 +1024,9 @@ a²+b²=1 ⇒ |a + b| ≤ 2 <b>Which is what we wanted to prove, therefor the im
 </li>
 </ul>
 </div>
-<div id="outline-container-orga59c0ad" class="outline-4">
-<h4 id="orga59c0ad">Reasoning by the Absurd:</h4>
-<div class="outline-text-4" id="text-orga59c0ad">
+<div id="outline-container-orgb9d2c9e" class="outline-4">
+<h4 id="orgb9d2c9e">Reasoning by the Absurd:</h4>
+<div class="outline-text-4" id="text-orgb9d2c9e">
 <p>
 To prove that a proposition is True, we suppose that it&rsquo;s False and we must come to a contradiction
 </p>
@@ -1037,8 +1037,8 @@ And to prove that an implication P ⇒ Q is true using the reasoning by the absu
 </p>
 </div>
 <ul class="org-ul">
-<li><a id="orgf8b9f83"></a>Example:<br />
-<div class="outline-text-5" id="text-orgf8b9f83">
+<li><a id="orgfbfd0bb"></a>Example:<br />
+<div class="outline-text-5" id="text-orgfbfd0bb">
 <p>
 Prove that this proposition is correct using the reasoning by the absurd : ∀x ∈ ℝ* , sqrt(1+x²) ≠ 1 + x²/2
 </p>
@@ -1056,17 +1056,17 @@ sqrt(1+x²) = 1 + x²/2 ; 1 + x² = (1+x²/2)² ; 1 + x² = 1 + x^4/4 + x²  ;
 </li>
 </ul>
 </div>
-<div id="outline-container-orgcc285c2" class="outline-4">
-<h4 id="orgcc285c2">Reasoning by contraposition:</h4>
-<div class="outline-text-4" id="text-orgcc285c2">
+<div id="outline-container-org8b209a6" class="outline-4">
+<h4 id="org8b209a6">Reasoning by contraposition:</h4>
+<div class="outline-text-4" id="text-org8b209a6">
 <p>
 If an implication P ⇒ Q is too hard to prove, we just have to prove not(Q) ⇒ not(P) is true !!! or in other words that both not(P) and not(Q) are true
 </p>
 </div>
 </div>
-<div id="outline-container-org2e67808" class="outline-4">
-<h4 id="org2e67808">Reasoning by counter example:</h4>
-<div class="outline-text-4" id="text-org2e67808">
+<div id="outline-container-org94c9a28" class="outline-4">
+<h4 id="org94c9a28">Reasoning by counter example:</h4>
+<div class="outline-text-4" id="text-org94c9a28">
 <p>
 To prove that a proposition ∀x ∈ E, P(x) is false, all we have to do is find a single value of x from E such as not(P(x)) is true
 </p>
@@ -1074,20 +1074,20 @@ To prove that a proposition ∀x ∈ E, P(x) is false, all we have to do is find
 </div>
 </div>
 </div>
-<div id="outline-container-org7440601" class="outline-2">
-<h2 id="org7440601">3eme Cours : <i>Oct 9</i></h2>
-<div class="outline-text-2" id="text-org7440601">
+<div id="outline-container-org0eabee1" class="outline-2">
+<h2 id="org0eabee1">3eme Cours : <i>Oct 9</i></h2>
+<div class="outline-text-2" id="text-org0eabee1">
 </div>
-<div id="outline-container-org70aa2db" class="outline-4">
-<h4 id="org70aa2db">Reasoning by recurrence :</h4>
-<div class="outline-text-4" id="text-org70aa2db">
+<div id="outline-container-orgdafe6b7" class="outline-4">
+<h4 id="orgdafe6b7">Reasoning by recurrence :</h4>
+<div class="outline-text-4" id="text-orgdafe6b7">
 <p>
 P is a propriety dependent of <b>n ∈ ℕ</b>. If for n0 ∈ ℕ P(n0) is true, and if for n ≥ n0 (P(n) ⇒ P(n+1)) is true. Then P(n) is true for n ≥ n0
 </p>
 </div>
 <ul class="org-ul">
-<li><a id="org52e5298"></a>Example:<br />
-<div class="outline-text-5" id="text-org52e5298">
+<li><a id="org9970baf"></a>Example:<br />
+<div class="outline-text-5" id="text-org9970baf">
 <p>
 Let&rsquo;s prove that ∀ n ≥ 1 , (n,k=1)Σk = [n(n+1)]/2
 </p>
@@ -1123,21 +1123,21 @@ For n ≥ 1. We assume that P(n) is true, OR : <b>(n, k=1)Σk = n(n+1)/2</b>. We
 </ul>
 </div>
 </div>
-<div id="outline-container-orga6a518d" class="outline-2">
-<h2 id="orga6a518d">4eme Cours : Chapitre 2 : Sets and Operations</h2>
-<div class="outline-text-2" id="text-orga6a518d">
+<div id="outline-container-org4d1906f" class="outline-2">
+<h2 id="org4d1906f">4eme Cours : Chapitre 2 : Sets and Operations</h2>
+<div class="outline-text-2" id="text-org4d1906f">
 </div>
-<div id="outline-container-org31e3615" class="outline-3">
-<h3 id="org31e3615">Definition of a set :</h3>
-<div class="outline-text-3" id="text-org31e3615">
+<div id="outline-container-orgd19c38e" class="outline-3">
+<h3 id="orgd19c38e">Definition of a set :</h3>
+<div class="outline-text-3" id="text-orgd19c38e">
 <p>
 A set is a collection of objects that share the sane propriety
 </p>
 </div>
 </div>
-<div id="outline-container-orgfa9bfd1" class="outline-3">
-<h3 id="orgfa9bfd1">Belonging, inclusion, and equality :</h3>
-<div class="outline-text-3" id="text-orgfa9bfd1">
+<div id="outline-container-orgcf58c48" class="outline-3">
+<h3 id="orgcf58c48">Belonging, inclusion, and equality :</h3>
+<div class="outline-text-3" id="text-orgcf58c48">
 <ol class="org-ol">
 <li>Let E be a set. If x is an element of E, we say that x belongs to E we write <b>x ∈ E</b>, and if it doesn&rsquo;t, we write <b>x ∉ E</b></li>
 <li>A set E is included in a set F if all elements of E are elements of F and we write <b>E ⊂ F ⇔ (∀x , x ∈ E ⇒ x ∈ F)</b>. We say that E is a subset of F, or a part of F. The negation of this propriety is : <b>E ⊄ F ⇔ ∃x , x ∈ E and x ⊄ F</b></li>
@@ -1146,13 +1146,13 @@ A set is a collection of objects that share the sane propriety
 </ol>
 </div>
 </div>
-<div id="outline-container-org2a19707" class="outline-3">
-<h3 id="org2a19707">Intersections and reunions :</h3>
-<div class="outline-text-3" id="text-org2a19707">
+<div id="outline-container-org939fd93" class="outline-3">
+<h3 id="org939fd93">Intersections and reunions :</h3>
+<div class="outline-text-3" id="text-org939fd93">
 </div>
-<div id="outline-container-org6a5f566" class="outline-4">
-<h4 id="org6a5f566">Intersection:</h4>
-<div class="outline-text-4" id="text-org6a5f566">
+<div id="outline-container-orge8ae0b6" class="outline-4">
+<h4 id="orge8ae0b6">Intersection:</h4>
+<div class="outline-text-4" id="text-orge8ae0b6">
 <p>
 E ∩ F = {x / x ∈ E AND x ∈ F} ; x ∈ E ∩ F ⇔ x ∈ F AND x ∈ F
 </p>
@@ -1163,9 +1163,9 @@ x ∉ E ∩ F ⇔ x ∉ E OR x ∉ F
 </p>
 </div>
 </div>
-<div id="outline-container-org9bc9aeb" class="outline-4">
-<h4 id="org9bc9aeb">Union:</h4>
-<div class="outline-text-4" id="text-org9bc9aeb">
+<div id="outline-container-org07c050a" class="outline-4">
+<h4 id="org07c050a">Union:</h4>
+<div class="outline-text-4" id="text-org07c050a">
 <p>
 E ∪ F = {x / x ∈ E OR x ∈ F} ;  x ∈ E ∪ F ⇔ x ∈ F OR x ∈ F
 </p>
@@ -1176,17 +1176,17 @@ x ∉ E ∪ F ⇔ x ∉ E AND x ∉ F
 </p>
 </div>
 </div>
-<div id="outline-container-org9a7f719" class="outline-4">
-<h4 id="org9a7f719">Difference between two sets:</h4>
-<div class="outline-text-4" id="text-org9a7f719">
+<div id="outline-container-org7ecf856" class="outline-4">
+<h4 id="org7ecf856">Difference between two sets:</h4>
+<div class="outline-text-4" id="text-org7ecf856">
 <p>
 E\F(Which is also written as : E - F) = {x / x ∈ E and x ∉ F}
 </p>
 </div>
 </div>
-<div id="outline-container-org5f5c721" class="outline-4">
-<h4 id="org5f5c721">Complimentary set:</h4>
-<div class="outline-text-4" id="text-org5f5c721">
+<div id="outline-container-orgad5f4da" class="outline-4">
+<h4 id="orgad5f4da">Complimentary set:</h4>
+<div class="outline-text-4" id="text-orgad5f4da">
 <p>
 If F ⊂ E. E - F is the complimentary of F in E.
 </p>
@@ -1197,52 +1197,52 @@ FCE = {x /x ∈ E AND x ∉ F} <b>ONLY WHEN F IS A SUBSET OF E</b>
 </p>
 </div>
 </div>
-<div id="outline-container-orga285d1d" class="outline-4">
-<h4 id="orga285d1d">Symentrical difference</h4>
-<div class="outline-text-4" id="text-orga285d1d">
+<div id="outline-container-org3e8e3b3" class="outline-4">
+<h4 id="org3e8e3b3">Symentrical difference</h4>
+<div class="outline-text-4" id="text-org3e8e3b3">
 <p>
 E Δ F = (E - F) ∪ (F - E) ; = (E ∪ F) - (E ∩ F)
 </p>
 </div>
 </div>
 </div>
-<div id="outline-container-orgc12e73b" class="outline-3">
-<h3 id="orgc12e73b">Proprieties :</h3>
-<div class="outline-text-3" id="text-orgc12e73b">
+<div id="outline-container-org8920c77" class="outline-3">
+<h3 id="org8920c77">Proprieties :</h3>
+<div class="outline-text-3" id="text-org8920c77">
 <p>
 Let E,F and G be 3 sets. We have :
 </p>
 </div>
-<div id="outline-container-org31d8697" class="outline-4">
-<h4 id="org31d8697">Commutativity:</h4>
-<div class="outline-text-4" id="text-org31d8697">
+<div id="outline-container-orgcb406ce" class="outline-4">
+<h4 id="orgcb406ce">Commutativity:</h4>
+<div class="outline-text-4" id="text-orgcb406ce">
 <p>
 E ∩ F = F ∩ E
 E ∪ F = F ∪ E
 </p>
 </div>
 </div>
-<div id="outline-container-org7080d99" class="outline-4">
-<h4 id="org7080d99">Associativity:</h4>
-<div class="outline-text-4" id="text-org7080d99">
+<div id="outline-container-orgfcaf63a" class="outline-4">
+<h4 id="orgfcaf63a">Associativity:</h4>
+<div class="outline-text-4" id="text-orgfcaf63a">
 <p>
 E ∩ (F ∩ G) = (E ∩ F) ∩ G
 E ∪ (F ∪ G) = (E ∪ F) ∪ G
 </p>
 </div>
 </div>
-<div id="outline-container-org13da04d" class="outline-4">
-<h4 id="org13da04d">Distributivity:</h4>
-<div class="outline-text-4" id="text-org13da04d">
+<div id="outline-container-org6ad9182" class="outline-4">
+<h4 id="org6ad9182">Distributivity:</h4>
+<div class="outline-text-4" id="text-org6ad9182">
 <p>
 E ∩ (F ∪ G) = (E ∩ F) ∪ (E ∩ G)
 E ∪ (F ∩ G) = (E ∪ F) ∩ (E ∪ G)
 </p>
 </div>
 </div>
-<div id="outline-container-orgaa33b71" class="outline-4">
-<h4 id="orgaa33b71">Lois de Morgan:</h4>
-<div class="outline-text-4" id="text-orgaa33b71">
+<div id="outline-container-org7a0450e" class="outline-4">
+<h4 id="org7a0450e">Lois de Morgan:</h4>
+<div class="outline-text-4" id="text-org7a0450e">
 <p>
 If E ⊂ G and F ⊂ G ;
 </p>
@@ -1252,33 +1252,33 @@ If E ⊂ G and F ⊂ G ;
 </p>
 </div>
 </div>
-<div id="outline-container-org7e7db42" class="outline-4">
-<h4 id="org7e7db42">An other one:</h4>
-<div class="outline-text-4" id="text-org7e7db42">
+<div id="outline-container-org44fd147" class="outline-4">
+<h4 id="org44fd147">An other one:</h4>
+<div class="outline-text-4" id="text-org44fd147">
 <p>
 E - (F ∩ G) = (E-F) ∪ (E-G) ;  E - (F ∪ G) = (E-F) ∩ (E-G)
 </p>
 </div>
 </div>
-<div id="outline-container-orgd02bd7f" class="outline-4">
-<h4 id="orgd02bd7f">An other one:</h4>
-<div class="outline-text-4" id="text-orgd02bd7f">
+<div id="outline-container-orgca3a4c6" class="outline-4">
+<h4 id="orgca3a4c6">An other one:</h4>
+<div class="outline-text-4" id="text-orgca3a4c6">
 <p>
 E ∩ ∅ = ∅ ; E ∪ ∅ = E
 </p>
 </div>
 </div>
-<div id="outline-container-org99eb39a" class="outline-4">
-<h4 id="org99eb39a">And an other one:</h4>
-<div class="outline-text-4" id="text-org99eb39a">
+<div id="outline-container-org6cd18a3" class="outline-4">
+<h4 id="org6cd18a3">And an other one:</h4>
+<div class="outline-text-4" id="text-org6cd18a3">
 <p>
 E ∩ (F Δ G) = (E ∩ F) Δ (E ∩ G)
 </p>
 </div>
 </div>
-<div id="outline-container-org3e9b2ef" class="outline-4">
-<h4 id="org3e9b2ef">And the last one:</h4>
-<div class="outline-text-4" id="text-org3e9b2ef">
+<div id="outline-container-org0889163" class="outline-4">
+<h4 id="org0889163">And the last one:</h4>
+<div class="outline-text-4" id="text-org0889163">
 <p>
 E Δ ∅ = E ; E Δ E = ∅
 </p>
@@ -1289,7 +1289,7 @@ E Δ ∅ = E ; E Δ E = ∅
 </div>
 <div id="postamble" class="status">
 <p class="author">Author: Crystal</p>
-<p class="date">Created: 2023-10-11 Wed 19:04</p>
+<p class="date">Created: 2023-10-13 Fri 16:58</p>
 </div>
 </body>
 </html>
\ No newline at end of file