// Numbas version: finer_feedback_settings
{"name": "2.6.8 Circle equation no 2", "extensions": [], "custom_part_types": [], "resources": [], "navigation": {"allowregen": true, "showfrontpage": false, "preventleave": false, "typeendtoleave": false}, "question_groups": [{"pickingStrategy": "all-ordered", "questions": [{"name": "2.6.8 Circle equation no 2", "tags": [], "metadata": {"description": "<p>Given a circle centre and a point on the circumference, write down the circle equation.</p>", "licence": "Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International"}, "statement": "<p>Obtain the equation of the circle which has centre $(\\var{centrex},\\var{centrey})$ and which passes through the point $(\\var{pointx},\\var{pointy})$.</p>", "advice": "<p>We need to compute the distance from the centre of the circle to the point on the circumference. This distance is the radius, $r$.</p>\n<p>$r=\\sqrt{\\left[(\\var{centrex})-(\\var{pointx})\\right]^2 + \\left[(\\var{centrey})-(\\var{pointy})\\right]^2}$</p>\n<p>$r=\\sqrt{\\var{radiussquared}}$ <span data-jme-visible=\"evalradius=intradius\">$=\\var{radius}$</span></p>\n<p>Hence the circle equation is $\\var{equation}$.</p>\n<p></p>", "rulesets": {}, "extensions": [], "builtin_constants": {"e": true, "pi,\u03c0": true, "i": true}, "constants": [], "variables": {"centrex": {"name": "centrex", "group": "Ungrouped variables", "definition": "random(-9,9)", "description": "", "templateType": "anything", "can_override": false}, "centrey": {"name": "centrey", "group": "Ungrouped variables", "definition": "random(-9..9)", "description": "", "templateType": "anything", "can_override": false}, "pointx": {"name": "pointx", "group": "Ungrouped variables", "definition": "random(-9..9)", "description": "", "templateType": "anything", "can_override": false}, "pointy": {"name": "pointy", "group": "Ungrouped variables", "definition": "random(-9..9)", "description": "", "templateType": "anything", "can_override": false}, "radiussquared": {"name": "radiussquared", "group": "Ungrouped variables", "definition": "(centrex-pointx)^2+(centrey-pointy)^2", "description": "", "templateType": "anything", "can_override": false}, "radius": {"name": "radius", "group": "Ungrouped variables", "definition": "simplify(expression(\"sqrt(\"+radiussquared+\")\"),\"sqrtSquare\")", "description": "", "templateType": "anything", "can_override": false}, "intradius": {"name": "intradius", "group": "Ungrouped variables", "definition": "floor(eval(radius))", "description": "", "templateType": "anything", "can_override": false}, "evalradius": {"name": "evalradius", "group": "Ungrouped variables", "definition": "eval(radius)", "description": "", "templateType": "anything", "can_override": false}, "equation": {"name": "equation", "group": "Ungrouped variables", "definition": "simplify(expression(\"(x-\" + centrex + \")^2+(y-\"+ centrey + \")^2 = \" + radiussquared  ),\"all\")", "description": "", "templateType": "anything", "can_override": false}}, "variablesTest": {"condition": "centrex<>pointx or centrey<>pointy", "maxRuns": 100}, "ungrouped_variables": ["centrex", "centrey", "pointx", "pointy", "radiussquared", "radius", "intradius", "evalradius", "equation"], "variable_groups": [], "functions": {}, "preamble": {"js": "", "css": ""}, "parts": [{"type": "jme", "useCustomName": false, "customName": "", "marks": 1, "scripts": {}, "customMarkingAlgorithm": "", "extendBaseMarkingAlgorithm": true, "unitTests": [], "showCorrectAnswer": true, "showFeedbackIcon": true, "variableReplacements": [], "variableReplacementStrategy": "originalfirst", "nextParts": [], "suggestGoingBack": false, "adaptiveMarkingPenalty": 0, "exploreObjective": null, "answer": "{equation}", "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": []}], "partsMode": "all", "maxMarks": 0, "objectives": [], "penalties": [], "objectiveVisibility": "always", "penaltyVisibility": "always", "type": "question", "contributors": [{"name": "Merryn Horrocks", "profile_url": "https://numbas.mathcentre.ac.uk/accounts/profile/4052/"}], "resources": []}]}], "contributors": [{"name": "Merryn Horrocks", "profile_url": "https://numbas.mathcentre.ac.uk/accounts/profile/4052/"}]}