// Numbas version: exam_results_page_options
{"name": "T6Q9 (custom feedback)", "extensions": [], "custom_part_types": [], "resources": [], "navigation": {"allowregen": true, "showfrontpage": false, "preventleave": false, "typeendtoleave": false}, "question_groups": [{"pickingStrategy": "all-ordered", "questions": [{"parts": [{"variableReplacementStrategy": "originalfirst", "prompt": "<p>$\\frac{\\partial K}{\\partial r} =$ [[0]]</p>", "showCorrectAnswer": true, "sortAnswers": false, "type": "gapfill", "unitTests": [], "customMarkingAlgorithm": "", "scripts": {}, "variableReplacements": [], "showFeedbackIcon": true, "marks": 0, "gaps": [{"variableReplacementStrategy": "originalfirst", "failureRate": 1, "checkVariableNames": false, "showPreview": true, "vsetRange": [0, 1], "type": "jme", "showCorrectAnswer": true, "checkingType": "absdiff", "checkingAccuracy": 0.001, "unitTests": [], "customMarkingAlgorithm": "malrules:\n  [\n    [\"15(r+s)^2*(r-s)^4\", \"Don't forget the product rule! Since this is one function of $r$ multiplied by another function of $r$, you need the product rule.\"]\n    ]\n\n\nparsed_malrules: \n    map(\n        [\"expr\":parse(x[0]),\"feedback\":x[1]],\n        x,\n        malrules\n    )\n\nagree_malrules (Do the student's answer and the expected answer agree on each of the sets of variable values?):\n    map(\n        len(filter(not x ,x,map(\n            try(\n                resultsEqual(unset(question_definitions,eval(studentexpr,vars)),unset(question_definitions,eval(malrule[\"expr\"],vars)),settings[\"checkingType\"],settings[\"checkingAccuracy\"]),\n                message,\n                false\n            ),\n            vars,\n            vset\n        )))<settings[\"failureRate\"],\n        malrule,\n        parsed_malrules\n    )\n\nmatched_malrules:\n  filter(x[0],x,zip(agree_malrules,parsed_malrules))\n  \nmalrule_feedback:\n    assert(numericallyCorrect,\n        assert(len(matched_malrules)=0,\n            set_credit(0,matched_malrules[0][1][\"feedback\"])\n        )\n    )\n\nmark:\n    apply(studentExpr);\n    apply(unexpectedVariables);\n    apply(numericallyCorrect);\n    apply(malrule_feedback);\n    apply(sameVars);\n    apply(failMinLength);\n    apply(failMaxLength);\n    apply(forbiddenStringsPenalty);\n    apply(requiredStringsPenalty) ", "scripts": {}, "variableReplacements": [], "expectedVariableNames": [], "marks": 1, "vsetRangePoints": 5, "answer": "5(r+s)^3*(r-s)^4+3(r+s)^2*(r-s)^5", "extendBaseMarkingAlgorithm": true, "showFeedbackIcon": true}], "extendBaseMarkingAlgorithm": true}, {"variableReplacementStrategy": "originalfirst", "prompt": "<p>$\\frac{\\partial K}{\\partial s}=$ [[0]]</p>", "showCorrectAnswer": true, "sortAnswers": false, "type": "gapfill", "unitTests": [], "customMarkingAlgorithm": "", "scripts": {}, "variableReplacements": [], "showFeedbackIcon": true, "marks": 0, "gaps": [{"variableReplacementStrategy": "originalfirst", "failureRate": 1, "checkVariableNames": false, "showPreview": true, "vsetRange": [0, 1], "type": "jme", "showCorrectAnswer": true, "checkingType": "absdiff", "checkingAccuracy": 0.001, "unitTests": [], "customMarkingAlgorithm": "malrules:\n  [\n    [\"15(r+s)^2*(r-s)^4\", \"There are two things to watch here. Firstly, don't forget the product rule! Since this is one function of $s$ multiplied by another function of $s$, you need the product rule. Secondly, when differentiating the $(r-s)^5$ term, don't forget to multiply by $\\\\frac{\\\\partial}{\\\\partial s} \\\\left( r-s \\\\right)$.\"],\n    [\"-15(r+s)^2*(r-s)^4\", \"Don't forget the product rule! Since this is one function of $s$ multiplied by another function of $s$, you need the product rule.\"],\n    [\"3(r+s)^2*(r-s)^5+5(r+s)^3*(r-s)^4\", \"Almost there. When differentiating the $(r-s)^5$ term, don't forget to multiply by $\\\\frac{\\\\partial}{\\\\partial s} \\\\left( r-s \\\\right)$.\"]\n    ]\n\n\nparsed_malrules: \n    map(\n        [\"expr\":parse(x[0]),\"feedback\":x[1]],\n        x,\n        malrules\n    )\n\nagree_malrules (Do the student's answer and the expected answer agree on each of the sets of variable values?):\n    map(\n        len(filter(not x ,x,map(\n            try(\n                resultsEqual(unset(question_definitions,eval(studentexpr,vars)),unset(question_definitions,eval(malrule[\"expr\"],vars)),settings[\"checkingType\"],settings[\"checkingAccuracy\"]),\n                message,\n                false\n            ),\n            vars,\n            vset\n        )))<settings[\"failureRate\"],\n        malrule,\n        parsed_malrules\n    )\n\nmatched_malrules:\n  filter(x[0],x,zip(agree_malrules,parsed_malrules))\n  \nmalrule_feedback:\n    assert(numericallyCorrect,\n        assert(len(matched_malrules)=0,\n            set_credit(0,matched_malrules[0][1][\"feedback\"])\n        )\n    )\n\nmark:\n    apply(studentExpr);\n    apply(unexpectedVariables);\n    apply(numericallyCorrect);\n    apply(malrule_feedback);\n    apply(sameVars);\n    apply(failMinLength);\n    apply(failMaxLength);\n    apply(forbiddenStringsPenalty);\n    apply(requiredStringsPenalty) ", "scripts": {}, "variableReplacements": [], "expectedVariableNames": [], "marks": 1, "vsetRangePoints": 5, "answer": "3(r+s)^2*(r-s)^5-5(r+s)^3*(r-s)^4", "extendBaseMarkingAlgorithm": true, "showFeedbackIcon": true}], "extendBaseMarkingAlgorithm": true}], "name": "T6Q9 (custom feedback)", "preamble": {"css": "", "js": ""}, "variable_groups": [], "extensions": [], "tags": [], "rulesets": {}, "advice": "", "metadata": {"description": "<p>Partial differentiation question with customised feedback to catch some common errors.</p>", "licence": "Creative Commons Attribution-NonCommercial 4.0 International"}, "ungrouped_variables": [], "variablesTest": {"condition": "", "maxRuns": 100}, "functions": {}, "variables": {}, "statement": "<p>Let $K=(r+s)^3(r-s)^5$. Find $\\frac{\\partial K}{\\partial r}$ and $\\frac{\\partial K}{\\partial s}$.</p>", "type": "question", "contributors": [{"name": "Clodagh Carroll", "profile_url": "https://numbas.mathcentre.ac.uk/accounts/profile/384/"}]}]}], "contributors": [{"name": "Clodagh Carroll", "profile_url": "https://numbas.mathcentre.ac.uk/accounts/profile/384/"}]}