// Numbas version: exam_results_page_options {"name": "Ecuaci\u00f3n de cuarto grado reducible a Cuadr\u00e1tica ", "extensions": [], "custom_part_types": [], "resources": [], "navigation": {"allowregen": true, "showfrontpage": false, "preventleave": false, "typeendtoleave": false}, "question_groups": [{"pickingStrategy": "all-ordered", "questions": [{"variablesTest": {"maxRuns": 100, "condition": ""}, "variable_groups": [{"name": "Unnamed group", "variables": []}], "preamble": {"js": "", "css": ""}, "statement": "
Resolver el siguiente ecuación:
\n\\[\\begin{eqnarray*}\\simplify[std]{x^4-{a^2+b^2}x^2+{(a*b)^2}}&=&{0}\\end{eqnarray*}\\]
", "ungrouped_variables": ["a", "b", "c"], "name": "Ecuaci\u00f3n de cuarto grado reducible a Cuadr\u00e1tica ", "functions": {}, "metadata": {"description": "Shows how to define variables to stop degenerate examples.
", "licence": "Creative Commons Attribution 4.0 International"}, "rulesets": {"std": ["All", "fractionnumbers"]}, "parts": [{"scripts": {}, "gaps": [{"scripts": {}, "checkvariablenames": false, "checkingtype": "absdiff", "showFeedbackIcon": true, "variableReplacements": [], "marks": 1, "expectedvariablenames": [], "showCorrectAnswer": true, "checkingaccuracy": 0.001, "answersimplification": "Std", "showpreview": true, "notallowed": {"partialCredit": 0, "strings": ["."], "showStrings": false, "message": "Input your answer as a fraction and not a decimal.
"}, "vsetrange": [0, 1], "type": "jme", "variableReplacementStrategy": "originalfirst", "answer": "{-b}", "vsetrangepoints": 5}, {"scripts": {}, "checkvariablenames": false, "checkingtype": "absdiff", "showFeedbackIcon": true, "variableReplacements": [], "marks": 1, "expectedvariablenames": [], "showCorrectAnswer": true, "checkingaccuracy": 0.001, "answersimplification": "Std", "showpreview": true, "notallowed": {"partialCredit": 0, "strings": ["."], "showStrings": false, "message": "Input your answer as a fraction and not a decimal.
"}, "vsetrange": [0, 1], "type": "jme", "variableReplacementStrategy": "originalfirst", "answer": "{-a}", "vsetrangepoints": 5}, {"scripts": {}, "checkvariablenames": false, "checkingtype": "absdiff", "showFeedbackIcon": true, "variableReplacements": [], "marks": 1, "expectedvariablenames": [], "showCorrectAnswer": true, "checkingaccuracy": 0.001, "answersimplification": "Std", "showpreview": true, "notallowed": {"partialCredit": 0, "strings": ["."], "showStrings": false, "message": "Input your answer as a fraction and not a decimal.
"}, "vsetrange": [0, 1], "type": "jme", "variableReplacementStrategy": "originalfirst", "answer": "{a}", "vsetrangepoints": 5}, {"scripts": {}, "checkvariablenames": false, "checkingtype": "absdiff", "showFeedbackIcon": true, "variableReplacements": [], "marks": 1, "expectedvariablenames": [], "showCorrectAnswer": true, "checkingaccuracy": 0.001, "answersimplification": "Std", "showpreview": true, "notallowed": {"partialCredit": 0, "strings": ["."], "showStrings": false, "message": "Input your answer as a fraction and not a decimal.
"}, "vsetrange": [0, 1], "type": "jme", "variableReplacementStrategy": "originalfirst", "answer": "{b}", "vsetrangepoints": 5}], "showFeedbackIcon": true, "variableReplacements": [], "marks": 0, "type": "gapfill", "showCorrectAnswer": true, "variableReplacementStrategy": "originalfirst", "prompt": "Observación: Para ingresar su respuesta, hágalo en el siguiente orden:
\n$x_1<x_2<x_3<x_4$
\n$x_1=$ [[0]] ; $x_2=$ [[1]] ; $x_3=$[[2]] ; $x_4=$[[3]]
\n\n"}], "extensions": [], "tags": [], "advice": "Utilicemos la sustitución $\\,x^2=t\\,$ en la ecuación:
\n\\[\\begin{eqnarray*}\\simplify[std]{x^4-{a^2+b^2}x^2+{(a*b)^2}}&=&{0}\\end{eqnarray*}\\]
\nNos queda:
\n\\[\\begin{eqnarray*}\\simplify[std]{t^2-{a^2+b^2}t+{(a*b)^2}}&=&{0}\\end{eqnarray*}\\]
\nEsta ecuación la podemos resolver factorizando.
\n\\begin{align}
(\\simplify{t-{a^2}})(\\simplify{t-{b^2}})&=\\,{0}
\\end{align}
\\[\\simplify{(t-{a^2}={0})} \\,\\,\\,\\,;\\,\\,\\, \\simplify{(t-{b^2}={0})} \\]
\n\\[\\simplify{(t={a^2})} \\,\\,\\,\\,;\\,\\,\\, \\simplify{(t={b^2})} \\]
\nAhora nos devolvemos con la sustitución $\\,x^2=t\\,$, de modo de encontrar los valores de la variable $x$:
\n\\[\\simplify{(x^2={a^2})} \\,\\,\\,\\,;\\,\\,\\, \\simplify{(x^2={b^2})} \\]
\nEstas ecuaciones las podemos resolver nuevamente factorizando:
\n\\[\\simplify{(x^2-{a^2}={0})} \\,\\,\\,\\,;\\,\\,\\, \\simplify{(x^2-{b^2}={0})} \\]
\n\\begin{align}
(\\simplify{x-{a}})(\\simplify{x+{a}})&=\\,{0}\\,\\,\\,\\,;\\,\\,\\,(\\simplify{x-{b}})(\\simplify{x+{b}})=\\,{0}
\\end{align}
\\begin{align}
\\simplify{(x={a})} \\,\\,\\,\\,;\\,\\,\\, \\simplify{x={-a}}\\,\\,\\,\\,;\\,\\,\\,\\simplify{(x={b})} \\,\\,\\,\\,;\\,\\,\\, \\simplify{x={-b}}
\\end{align}
Finalmente ordenamos las soluciones de menor a mayor como lo pide el enunciado:
\n\\begin{align}
\\simplify{(x_1={-b})} \\,\\,\\,\\,;\\,\\,\\, \\simplify{x_2={-a}}\\,\\,\\,\\,;\\,\\,\\,\\simplify{(x_3={a})} \\,\\,\\,\\,;\\,\\,\\, \\simplify{x_4={b}}
\\end{align}