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\\[ \\int u\\frac{dv}{dx} dx = uv - \\int v \\frac{du}{dx} dx. \\]
\nWe choose $u = \\simplify[std]{({a}x+{b})}$ and $\\displaystyle \\frac{dv}{dx} = \\simplify[std]{cos({c}*x+{d})}$.
\nSo $\\displaystyle \\frac{du}{dx} = \\simplify[std]{{a}}$ and $\\displaystyle v = \\simplify[std]{(1/{c})*sin({c}*x+{d})}$.
\nHence,
\\[ \\begin{eqnarray} \\int \\simplify[std]{({a}*x+{b})*cos({c}*x+{d})} dx &=& uv - \\int v \\frac{du}{dx} dx \\\\ &=& \\simplify[std]{(({a}*x+{b})/{c})*sin({c}*x+{d}) - ({a}/{c})*Int(sin({c}*x+{d}),x)} \\\\ &=& \\simplify[std]{(({a}x+{b})/{c})*sin({c}*x+{d}) +({a}/{c^2})*cos({c}*x+{d}) + C} \\end{eqnarray} \\]
$I=\\displaystyle \\int \\simplify[std]{({a}x+{b})*cos({c}x+{d})} dx $
\nThe formula for integration by parts is
\n\\[ \\int u\\frac{dv}{dx} dx = uv - \\int v \\frac{du}{dx} dx. \\]
\nWhat is the most suitable choice for $u$ and $\\frac{dv}{dx}$?
\n$u =\\;$[[0]]
\n$\\frac{dv}{dx} =\\;$[[1]]
\n", "sortAnswers": false, "showFeedbackIcon": true, "type": "gapfill", "customMarkingAlgorithm": "", "extendBaseMarkingAlgorithm": true, "variableReplacementStrategy": "originalfirst", "scripts": {}, "useCustomName": false}, {"unitTests": [], "customName": "", "marks": 0, "gaps": [{"unitTests": [], "checkingAccuracy": 0.001, "customName": "", "marks": 1, "variableReplacements": [], "showCorrectAnswer": true, "showFeedbackIcon": true, "type": "jme", "failureRate": 1, "checkVariableNames": false, "customMarkingAlgorithm": "", "checkingType": "absdiff", "extendBaseMarkingAlgorithm": true, "valuegenerators": [], "vsetRange": [0, 1], "variableReplacementStrategy": "originalfirst", "scripts": {}, "showPreview": true, "useCustomName": false, "answer": "{a}", "vsetRangePoints": 5}, {"unitTests": [], "checkingAccuracy": 0.001, "customName": "", "marks": 1, "variableReplacements": [], "showCorrectAnswer": true, "showFeedbackIcon": true, "type": "jme", "failureRate": 1, "checkVariableNames": false, "customMarkingAlgorithm": "", "checkingType": "absdiff", "extendBaseMarkingAlgorithm": true, "valuegenerators": [{"value": "", "name": "x"}], "vsetRange": [0, 1], "variableReplacementStrategy": "originalfirst", "scripts": {}, "showPreview": true, "useCustomName": false, "answer": "1/{c}sin({c}x+{d})", "vsetRangePoints": 5}], "variableReplacements": [], "showCorrectAnswer": true, "prompt": "Hence find $\\frac{du}{dx} =\\;$[[0]]
\n$v =\\;$[[1]]
", "sortAnswers": false, "showFeedbackIcon": true, "type": "gapfill", "customMarkingAlgorithm": "", "extendBaseMarkingAlgorithm": true, "variableReplacementStrategy": "originalfirst", "scripts": {}, "useCustomName": false}, {"unitTests": [], "customName": "", "marks": 0, "gaps": [{"unitTests": [], "checkingAccuracy": 0.001, "customName": "", "marks": 1, "variableReplacements": [], "showCorrectAnswer": true, "showFeedbackIcon": true, "type": "jme", "failureRate": 1, "checkVariableNames": false, "customMarkingAlgorithm": "", "checkingType": "absdiff", "extendBaseMarkingAlgorithm": true, "valuegenerators": [{"value": "", "name": "x"}], "vsetRange": [0, 1], "variableReplacementStrategy": "originalfirst", "scripts": {}, "showPreview": true, "useCustomName": false, "answer": "({a}x+{b})/{c}sin({c}x+{d})", "vsetRangePoints": 5}, {"unitTests": [], "checkingAccuracy": 0.001, "customName": "", "marks": 1, "variableReplacements": [], "showCorrectAnswer": true, "showFeedbackIcon": true, "type": "jme", "failureRate": 1, "checkVariableNames": false, "customMarkingAlgorithm": "", "checkingType": "absdiff", "extendBaseMarkingAlgorithm": true, "valuegenerators": [{"value": "", "name": "x"}], "vsetRange": [0, 1], "variableReplacementStrategy": "originalfirst", "scripts": {}, "showPreview": true, "useCustomName": false, "answer": "-{a}/{c}^2cos({c}x+{d})", "vsetRangePoints": 5}], "variableReplacements": [], "showCorrectAnswer": true, "prompt": "Hence find $uv =\\;$[[0]]
\n$\\int v\\frac{du}{dx}\\mathrm{d}x = \\;$[[1]]$+C$
", "sortAnswers": false, "showFeedbackIcon": true, "type": "gapfill", "customMarkingAlgorithm": "", "extendBaseMarkingAlgorithm": true, "variableReplacementStrategy": "originalfirst", "scripts": {}, "useCustomName": false}, {"unitTests": [], "customName": "", "marks": 0, "gaps": [{"checkingAccuracy": 0.001, "notallowed": {"message": "Do not input numbers as decimals, only as integers without the decimal point, or fractions
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\n$I=\\displaystyle \\int \\simplify[std]{({a}x+{b})*cos({c}x+{d})} dx = \\int u\\frac{dv}{dx} dx = uv - \\int v \\frac{du}{dx} dx = \\;$[[0]]$+C$
\nInput all numbers as fractions or integers and not decimals.
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", "licence": "Creative Commons Attribution 4.0 International"}, "functions": {}, "variables": {"d": {"definition": "s2*random(1..9)", "templateType": "anything", "group": "Ungrouped variables", "description": "", "name": "d"}, "s1": {"definition": "random(1,-1)", "templateType": "anything", "group": "Ungrouped variables", "description": "", "name": "s1"}, "c": {"definition": "random(2..5)", "templateType": "anything", "group": "Ungrouped variables", "description": "", "name": "c"}, "s2": {"definition": "random(1,-1)", "templateType": "anything", "group": "Ungrouped variables", "description": "", "name": "s2"}, "a": {"definition": "random(2..5)", "templateType": "anything", "group": "Ungrouped variables", "description": "", "name": "a"}, "b": {"definition": "s1*random(1..9)", "templateType": "anything", "group": "Ungrouped variables", "description": "", "name": "b"}}, "variablesTest": {"condition": "", "maxRuns": 100}, "statement": "Find the following indefinite integral.
\nInput all numbers as fractions or integers and not decimals.
\nInput the constant of integration as $C$.
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