// Numbas version: exam_results_page_options {"name": "Luis's copy of Luis's copy of Integration of fraction with power in denominator", "extensions": [], "custom_part_types": [], "resources": [], "navigation": {"allowregen": true, "showfrontpage": false, "preventleave": false, "typeendtoleave": false}, "question_groups": [{"pickingStrategy": "all-ordered", "questions": [{"variables": {"r": {"definition": "s2*random(1..5)", "description": "", "group": "Ungrouped variables", "templateType": "anything", "name": "r"}, "s2": {"definition": "random(1,-1)", "description": "", "group": "Ungrouped variables", "templateType": "anything", "name": "s2"}, "s1": {"definition": "random(1,-1)", "description": "", "group": "Ungrouped variables", "templateType": "anything", "name": "s1"}, "b": {"definition": "m*a", "description": "", "group": "Ungrouped variables", "templateType": "anything", "name": "b"}, "n": {"definition": "3", "description": "", "group": "Ungrouped variables", "templateType": "anything", "name": "n"}, "a": {"definition": "random(2..5)", "description": "", "group": "Ungrouped variables", "templateType": "anything", "name": "a"}, "m": {"definition": "s1*random(1..4)", "description": "", "group": "Ungrouped variables", "templateType": "anything", "name": "m"}, "d": {"definition": "random(1..5)", "description": "", "group": "Ungrouped variables", "templateType": "anything", "name": "d"}, "c": {"definition": "m*d+r", "description": "", "group": "Ungrouped variables", "templateType": "anything", "name": "c"}}, "ungrouped_variables": ["a", "c", "b", "d", "s2", "s1", "m", "n", "r"], "parts": [{"unitTests": [], "gaps": [{"unitTests": [], "checkingType": "absdiff", "showPreview": true, "expectedVariableNames": [], "answer": "({-m}/{n-2})*x-{m*d*(n-1)+r*(n-2)}/{(n-2)*(n-1)*a}", "showFeedbackIcon": true, "vsetRangePoints": 5, "notallowed": {"message": "

Do not input numbers as decimals, only as integers without the decimal point, or fractions

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$ I = \\ displaystyle \\ int \\ simplify [std] {({b} * x + {c}) / (({a} * x + {d}) ^ {n})} dx $

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Se le da que \\ [I = \\ simplify [std] {g (x) * ({a} x + {d}) ^ {1-n}} + C \\] para un polinomio $ g (x) $.

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Tienes que encontrar $ g (x) $.

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$ g (x) = \\; $Gap 0

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Recuerda ingresar todos los números como números enteros o fracciones.

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Encuentra la siguiente integral indefinida.

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Ingrese todos los números como números enteros o fracciones, no como decimales.

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$\\displaystyle \\int \\frac{bx+c}{(ax+d)^n} dx=g(x)(ax+d)^{1-n}+C$  for a polynomial $g(x)$. Find $g(x)$.

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Let $y = \\simplify[std]{{a}*x+{d}}$.

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Then $x=\\frac{1}{\\var{a}}\\simplify[std]{(y-{d})}$ and so we have the numerator $\\simplify[std]{{b}*x+{c}}$ becomes in terms of $y$:

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$\\simplify[std]{{b}*x+{c} = {b}*1/{a}*(y-{d})+{c}= {m}y+{r}}$ and so

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\\[\\simplify[std]{({b}*x+{c})/(({a}*x+{d})^{n})} = \\simplify[std]{({m}*y+{r})/(y^{n})={m}/y^{n-1}+{r}/y^{n}}\\]

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Now,
\\[\\int \\simplify[std]{({b}x+{c})/({a}*x+{d})^{n}} dx = \\int \\left(\\simplify[std]{{m}/y^{n-1}+{r}/y^{n}} \\right)\\frac{dx}{dy} dy \\]

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Since $\\displaystyle x = \\simplify[std]{(y-{d})/{a}}$ then $\\displaystyle \\frac{dx}{dy} = \\frac{1}{\\var{a}}$.

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We can now calculate the desired integral:

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\\[ \\begin{eqnarray*} \\int \\left(\\simplify[std]{{m}/y^{n-1}+{r}/y^{n}}\\right) \\frac{dx}{dy} dy &=&\\frac{1}{\\var{a}}\\left(\\int \\simplify[std]{{m}/y^{n-1}}\\;dy+\\int \\simplify[std]{{r}/y^{n}}\\;dy \\right)\\\\ &=&\\frac{1}{\\var{a}}\\left(\\simplify[std]{{-m}/({n-2}*y^{n-2})+ {-r}/({n-1}*y^{n-1})}\\right) + C \\\\ &=& \\simplify[std]{(-{m})/({a*(n-2)}*({a}*x+{d})^{n-2})+(-{r})/({a*(n-1)}*({a}*x+{d})^{n-1}) + C}\\\\ &=&\\simplify[std]{1/({a}x+{d})^{n-1}*(({-m}/{a*(n-2)})*({a}x+{d})-{r}/({a*(n-1)}))}\\\\ &=&\\simplify[std]{1/({a}x+{d})^{n-1}*(({-m}/{(n-2)})*x+{-m*d*(n-1)-r*(n-2)}/{(n-2)*(n-1)*a})} \\end{eqnarray*} \\]
Hence \\[g(x)=\\simplify[std]{({-m}/{(n-2)})*x+{-m*d*(n-1)-r*(n-2)}/{(n-2)*(n-1)*a}}\\]

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