// Numbas version: finer_feedback_settings {"name": "Unit 4 - Which quadratic function is shown by the parabola?", "extensions": ["jsxgraph"], "custom_part_types": [], "resources": [], "navigation": {"allowregen": true, "showfrontpage": false, "preventleave": false, "typeendtoleave": false}, "question_groups": [{"pickingStrategy": "all-ordered", "questions": [{"rulesets": {}, "parts": [{"showFeedbackIcon": true, "maxMarks": 0, "variableReplacementStrategy": "originalfirst", "displayColumns": 0, "type": "1_n_2", "matrix": "[2,0,0,0,0]", "steps": [{"variableReplacements": [], "showFeedbackIcon": true, "scripts": {}, "variableReplacementStrategy": "originalfirst", "marks": 0, "prompt": "
You can narrow down the choices by checking points where the curve intersects the axes, in particular, the $y$-axis intercept. In addition, the $x$-coordinate of the vertex of the parabola is $x=\\frac{-b}{2a}$, when the curve is written in the standard form $y=ax^2+bx+c$. The line $x=\\frac{-b}{2a}$ is also the vertical line of symmetry for the curve.
", "showCorrectAnswer": true, "type": "information"}], "displayType": "radiogroup", "stepsPenalty": "1", "variableReplacements": [], "choices": "[function1,function2,function3,function4,function5]", "scripts": {}, "prompt": "Decide which of the following expressions for $f(x)$ corresponds to the parabola shown.
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{drawgraph()} | \n
Tests the ability to match a quadratic function to a given parabola.
", "licence": "Creative Commons Attribution 4.0 International"}, "type": "question", "contributors": [{"name": "Richard Miles", "profile_url": "https://numbas.mathcentre.ac.uk/accounts/profile/882/"}]}]}], "contributors": [{"name": "Richard Miles", "profile_url": "https://numbas.mathcentre.ac.uk/accounts/profile/882/"}]}