// Numbas version: exam_results_page_options
{"name": "identify the exponential formula", "extensions": ["geogebra"], "custom_part_types": [], "resources": [], "navigation": {"allowregen": true, "showfrontpage": false, "preventleave": false, "typeendtoleave": false}, "question_groups": [{"pickingStrategy": "all-ordered", "questions": [{"name": "identify the exponential formula", "tags": [], "metadata": {"description": "<p>Students are shown an exponential graph and asked to choose the correct formula for the graph.</p>", "licence": "Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International"}, "statement": "<p>{geogebra_applet('https://www.geogebra.org/m/fyfns8hu',defs)}</p>", "advice": "<p>The exponential curve is {direction}. So we are looking for a formula that has {pmprefix} before the $x$.</p>\n<p></p>\n<p>When $x=0$, $y=\\var{ek}$. So we are looking for a formula in which $k=\\var{ek}$, that is, $y = \\var{ek} \\times a^{\\var{chooseprefix} x}$.</p>\n<p></p>\n<p>Thus, the formula we need is&nbsp;$y = \\var{ek} \\times \\var{ea}^{\\var{chooseprefix} x}&nbsp;\\var{choosesign}$</p>", "rulesets": {}, "extensions": ["geogebra"], "builtin_constants": {"e": true, "pi,\u03c0": true, "i": true}, "constants": [], "variables": {"ea": {"name": "ea", "group": "Ungrouped variables", "definition": "random(2..10)", "description": "", "templateType": "anything", "can_override": false}, "ek": {"name": "ek", "group": "Ungrouped variables", "definition": "random(1..5)", "description": "", "templateType": "anything", "can_override": false}, "chooseprefix": {"name": "chooseprefix", "group": "Ungrouped variables", "definition": "prefix[(eb+1)/2]", "description": "", "templateType": "anything", "can_override": false}, "choosesign": {"name": "choosesign", "group": "Ungrouped variables", "definition": "sign[sgn(ec)+1]", "description": "", "templateType": "anything", "can_override": false}, "eb": {"name": "eb", "group": "Ungrouped variables", "definition": "random(-1,1)", "description": "", "templateType": "anything", "can_override": false}, "ec": {"name": "ec", "group": "Ungrouped variables", "definition": "random(-1..3)", "description": "", "templateType": "anything", "can_override": false}, "prefix": {"name": "prefix", "group": "Ungrouped variables", "definition": "['-','']", "description": "", "templateType": "anything", "can_override": false}, "": {"name": "", "group": "Ungrouped variables", "definition": "", "description": "", "templateType": "anything", "can_override": false}, "sign": {"name": "sign", "group": "Ungrouped variables", "definition": "['{ec}','','+ {ec}']", "description": "", "templateType": "anything", "can_override": false}, "ek2": {"name": "ek2", "group": "Ungrouped variables", "definition": "2*ek", "description": "", "templateType": "anything", "can_override": false}, "ek3": {"name": "ek3", "group": "Ungrouped variables", "definition": "ek/2", "description": "", "templateType": "anything", "can_override": false}, "ec2": {"name": "ec2", "group": "Ungrouped variables", "definition": "ec*(-1)", "description": "", "templateType": "anything", "can_override": false}, "defs": {"name": "defs", "group": "Ungrouped variables", "definition": "[\n  ['a',ea],['b',eb],['c',ec],['k',ek],['xm',6],['ym',40]\n  ]", "description": "", "templateType": "anything", "can_override": false}, "choosesign2": {"name": "choosesign2", "group": "Ungrouped variables", "definition": "sign2[sgn(ec2)+1]", "description": "", "templateType": "anything", "can_override": false}, "sign2": {"name": "sign2", "group": "Ungrouped variables", "definition": "['{ec2}','','+ {ec2}']", "description": "", "templateType": "anything", "can_override": false}, "directions": {"name": "directions", "group": "Ungrouped variables", "definition": "['decreasing','increasing']", "description": "", "templateType": "anything", "can_override": false}, "direction": {"name": "direction", "group": "Ungrouped variables", "definition": "directions[(eb+1)/2]", "description": "", "templateType": "anything", "can_override": false}, "pmprefixes": {"name": "pmprefixes", "group": "Ungrouped variables", "definition": "['a -','nothing (meaning +)']", "description": "", "templateType": "anything", "can_override": false}, "pmprefix": {"name": "pmprefix", "group": "Ungrouped variables", "definition": "pmprefixes[(eb+1)/2]", "description": "", "templateType": "anything", "can_override": false}}, "variablesTest": {"condition": "", "maxRuns": 100}, "ungrouped_variables": ["ek", "ea", "chooseprefix", "choosesign", "eb", "ec", "prefix", "", "sign", "ek2", "ek3", "ec2", "defs", "choosesign2", "sign2", "directions", "direction", "pmprefixes", "pmprefix"], "variable_groups": [], "functions": {}, "preamble": {"js": "", "css": ""}, "parts": [{"type": "1_n_2", "useCustomName": false, "customName": "", "marks": 0, "scripts": {}, "customMarkingAlgorithm": "", "extendBaseMarkingAlgorithm": true, "unitTests": [], "showCorrectAnswer": true, "showFeedbackIcon": true, "variableReplacements": [], "variableReplacementStrategy": "originalfirst", "nextParts": [], "suggestGoingBack": false, "adaptiveMarkingPenalty": 0, "exploreObjective": null, "prompt": "<p>Which&nbsp;equation describes this exponential graph?</p>", "minMarks": 0, "maxMarks": 0, "shuffleChoices": true, "displayType": "radiogroup", "displayColumns": 0, "showCellAnswerState": true, "choices": ["$y = \\var{ek} \\times \\var{ea}^{\\var{chooseprefix} x}&nbsp;\\var{choosesign}$", "$y = \\var{ek2} \\times \\var{ea}^{\\var{chooseprefix} x}&nbsp;\\var{choosesign}$", "$y = \\var{ek3} \\times \\var{ea}^{\\var{chooseprefix} x}&nbsp;\\var{choosesign}$", "$y = \\var{ek2} \\times \\var{ea}^{\\var{chooseprefix} x}&nbsp;\\var{choosesign2}$"], "matrix": ["1", 0, 0, 0], "distractors": ["", "", "", ""]}], "partsMode": "all", "maxMarks": 0, "objectives": [], "penalties": [], "objectiveVisibility": "always", "penaltyVisibility": "always", "contributors": [{"name": "Merryn Horrocks", "profile_url": "https://numbas.mathcentre.ac.uk/accounts/profile/4052/"}]}]}], "contributors": [{"name": "Merryn Horrocks", "profile_url": "https://numbas.mathcentre.ac.uk/accounts/profile/4052/"}]}