// Numbas version: exam_results_page_options
{"name": "Mark the logarithm of a negative number: correct if the exponentials of the student's answer and expected answer are equal", "extensions": [], "custom_part_types": [], "resources": [], "navigation": {"allowregen": true, "showfrontpage": false, "preventleave": false, "typeendtoleave": false}, "question_groups": [{"pickingStrategy": "all-ordered", "questions": [{"name": "Mark the logarithm of a negative number: correct if the exponentials of the student's answer and expected answer are equal", "tags": [], "metadata": {"description": "<p>The expected answer involves the logarithm of a negative number, which doesn't have a unique solution.</p>\n<p>The part's marking algorithm evaluates the exponential of the student's answer and the expected answer, and compares those.</p>", "licence": "Creative Commons Attribution 4.0 International"}, "statement": "", "advice": "", "rulesets": {}, "extensions": [], "builtin_constants": {"e": true, "pi,\u03c0": true, "i": true}, "constants": [], "variables": {}, "variablesTest": {"condition": "", "maxRuns": 100}, "ungrouped_variables": [], "variable_groups": [], "functions": {}, "preamble": {"js": "", "css": ""}, "parts": [{"type": "jme", "useCustomName": false, "customName": "", "marks": 1, "scripts": {}, "customMarkingAlgorithm": "studentCompare: substitute([\"expr\":base_studentCompare], expression(\"exp(expr)\"))\n\ncorrectCompare: substitute([\"expr\":base_correctCompare], expression(\"exp(expr)\"))", "extendBaseMarkingAlgorithm": true, "unitTests": [{"variables": [], "name": "ln(-1/(x+5)) is correct", "answer": {"valid": true, "value": "ln(-1/(x+5))"}, "notes": [{"name": "mark", "expected": {"value": "nothing", "messages": [{"op": "add_credit", "credit": 1, "message": "Your answer is numerically correct.\n\nYou were awarded <strong>1</strong> mark.", "reason": "correct", "credit_change": "positive"}], "warnings": [], "error": "", "valid": true, "credit": 1}}, {"name": "agree", "expected": {"value": "[ true, true, true, true, true ]", "messages": [], "warnings": [], "error": "", "valid": true, "credit": 1}}]}, {"variables": [], "name": "ln(-1/(-x-5)) is marked incorrect", "answer": {"valid": true, "value": "ln(-1/(-x-5))"}, "notes": [{"name": "mark", "expected": {"value": "nothing", "messages": [{"op": "add_credit", "credit": 0, "message": "Your answer is incorrect.", "reason": "incorrect", "credit_change": "negative"}], "warnings": [], "error": "", "valid": true, "credit": 0}}, {"name": "agree", "expected": {"value": "[ false, false, false, false, false ]", "messages": [], "warnings": [], "error": "", "valid": true, "credit": 1}}]}], "showCorrectAnswer": true, "showFeedbackIcon": true, "variableReplacements": [], "variableReplacementStrategy": "originalfirst", "nextParts": [], "suggestGoingBack": false, "adaptiveMarkingPenalty": 0, "exploreObjective": null, "prompt": "<p>The answer is $-\\ln(-x-5)$. Try writing $\\ln\\left(\\frac{-1}{-x-5}\\right)$.</p>", "answer": "-ln(-x-5)", "showPreview": true, "checkingType": "absdiff", "checkingAccuracy": 0.001, "failureRate": 1, "vsetRangePoints": 5, "vsetRange": [0, 1], "checkVariableNames": false, "singleLetterVariables": false, "allowUnknownFunctions": true, "implicitFunctionComposition": false, "caseSensitive": false, "valuegenerators": [{"name": "x", "value": ""}]}], "partsMode": "all", "maxMarks": 0, "objectives": [], "penalties": [], "objectiveVisibility": "always", "penaltyVisibility": "always", "contributors": [{"name": "Christian Lawson-Perfect", "profile_url": "https://numbas.mathcentre.ac.uk/accounts/profile/7/"}]}]}], "contributors": [{"name": "Christian Lawson-Perfect", "profile_url": "https://numbas.mathcentre.ac.uk/accounts/profile/7/"}]}