// Numbas version: finer_feedback_settings
{"name": "Sketching graphs: which graphs are logarithmic", "extensions": ["jsxgraph"], "custom_part_types": [], "resources": [], "navigation": {"allowregen": true, "showfrontpage": false, "preventleave": false, "typeendtoleave": false}, "question_groups": [{"pickingStrategy": "all-ordered", "questions": [{"functions": {"plot": {"definition": "// Max and min x and y values for the axis.\nvar x_min = -10;\nvar x_max = 10;\nvar y_min = -15;\nvar y_max = 15;\n\n\n// First, make the JSXGraph board.\nvar div = Numbas.extensions.jsxgraph.makeBoard(\n  '300px',\n  '300px',\n {\n   boundingBox: [x_min,y_max,x_max,y_min],\n   axis: false,\n   showNavigation: false,\n   grid: false,\n   axis:false,\n }\n);\n\n\n\n// div.board is the object created by JSXGraph, which you use to \n// manipulate elements\nvar board = div.board; \n\n// create the x-axis and y-axis\nvar xaxis = board.create('line',[[0,0],[1,0]], { strokeColor: 'black', fixed: true});\n//var xticks = board.create('ticks',[xaxis,1],{\n//  drawLabels: true,\n//  label: {offset: [-4, -10]},\n//  minorTicks: 0\n//});\n\n// create the y-axis\nvar yaxis = board.create('line',[[0,0],[0,1]], { strokeColor: 'black', fixed: true });\n\n\n\n\n// Plot the function.\n\n\n//Define function depending on value of n.\nswitch(n) {\n    case 0:\n    var f = function(x) {return  Math.log(b*x+c);  }\n        break;\n    \n    case 1:\n    var f = function(x) {return Math.pow(2,b*x)*a+c; }\n        break;\n    \n    case 2:\n    var f = function(x) {return a*x+b;}\n        break;\n    \n    case 3:\n    var f = function(x) {return a*(x-b)*(x-b)*(x-b)-a*c*(x-b)+b}\n        break;\n    \n    case 4:\n    var f = function(x) {return a*(x-b)*(x-b)-c*(x-b);}\n    break;\n    \n}\n\n    board.create('functiongraph', [f], {strokeWidth:3,strokeColor:'black'});\n\nreturn div;\n\n\n\n// Plot coordinates.\n//    board.create('circle',[[x0,y0],0.1],{color:'red'});\n//    board.create('text',[x0,y0+0.3,'A']);\n//    board.create('circle',[[x1,y1],0.1],{color:'red'});\n//    board.create('text',[x1,y1+0.3,'B']);\n//    board.create('circle',[[x2,y2],0.1],{color:'red'});\n//    board.create('text',[x2,y2+0.3,'C']);\n\nreturn div;", "type": "html", "parameters": [["n", "number"], ["a", "number"], ["b", "number"], ["c", "number"]], "language": "javascript"}}, "tags": [], "variablesTest": {"maxRuns": 100, "condition": ""}, "metadata": {"licence": "Creative Commons Attribution 4.0 International", "description": "<p>Several graphs are drawn. Student should select those that are&nbsp;logarithmic</p>"}, "rulesets": {}, "preamble": {"css": "", "js": ""}, "extensions": ["jsxgraph"], "advice": "<p>See Lecture 8.3 for shapes of graphs of standard functions.&nbsp; A key feature of&nbsp;logarithmic graphs is that they have a vertical asymptote.</p>", "ungrouped_variables": [], "variable_groups": [{"name": "part a", "variables": ["a", "b", "c", "marks", "n", "min"]}], "statement": "<p>This is a non-calculator question.</p>", "name": "Sketching graphs: which graphs are logarithmic", "parts": [{"extendBaseMarkingAlgorithm": true, "warningType": "none", "displayColumns": 0, "variableReplacementStrategy": "originalfirst", "showFeedbackIcon": true, "shuffleChoices": true, "maxAnswers": 0, "displayType": "checkbox", "marks": 0, "customMarkingAlgorithm": "", "showCorrectAnswer": true, "variableReplacements": [], "type": "m_n_2", "matrix": "marks", "unitTests": [], "choices": ["<p>{plot(n[0],a[0],b[0],c[0])}</p>", "<p>{plot(n[1],a[1],b[1],c[1])}</p>", "<p>{plot(n[2],a[2],b[2],c[2])}</p>", "<p>{plot(n[3],-a[3],b[3],c[3])}</p>", "<p>{plot(n[4],a[4],b[4],c[4])}</p>"], "minAnswers": "{min}", "maxMarks": 0, "scripts": {}, "prompt": "<p>Which of the following look like graphs of a&nbsp;logarithmic function?&nbsp; (Remember to include transformed versions).</p>", "minMarks": 0}], "variables": {"min": {"definition": "if(n[2]=0,3,2)", "group": "part a", "description": "", "name": "min", "templateType": "anything"}, "n": {"definition": "[0,0,random(0..3),random(2..4),1]", "group": "part a", "description": "", "name": "n", "templateType": "anything"}, "b": {"definition": "shuffle([1,1,-1,-1,-1])", "group": "part a", "description": "", "name": "b", "templateType": "anything"}, "a": {"definition": "shuffle([1,1,1,2,2])", "group": "part a", "description": "", "name": "a", "templateType": "anything"}, "c": {"definition": "shuffle([-3,-1,0,2,4])", "group": "part a", "description": "", "name": "c", "templateType": "anything"}, "marks": {"definition": "[2/min,2/min,if(n[2]=0,2/min,-2),-2,-2]", "group": "part a", "description": "", "name": "marks", "templateType": "anything"}}, "type": "question", "contributors": [{"name": "Lovkush Agarwal", "profile_url": "https://numbas.mathcentre.ac.uk/accounts/profile/1358/"}]}]}], "contributors": [{"name": "Lovkush Agarwal", "profile_url": "https://numbas.mathcentre.ac.uk/accounts/profile/1358/"}]}