// Numbas version: exam_results_page_options {"name": "Even Functions", "extensions": ["jsxgraph"], "custom_part_types": [], "resources": [], "navigation": {"allowregen": true, "showfrontpage": false, "preventleave": false, "typeendtoleave": false}, "question_groups": [{"pickingStrategy": "all-ordered", "questions": [{"advice": "
Suppose that the point \\(A\\) has coordinates \\((\\var{x1}, \\var{a*x1^2})\\). Then by the symmetry of the graph the point \\(B\\) has coordinates \\((\\var{-1*x1}, \\var{a*x1^2})\\).
", "statement": "Geometrically, a function is called even if it is symmetric in the
Here the line from \\(A\\) to the vertical axis is shown as a solid line, and the reflection from the axis to \\(B\\) is shown as a dashed line.
\n{graph(a)}
\n\\(f(-x) \\equiv f(x).\\)
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"}, "extensions": ["jsxgraph"], "variables": {"a": {"templateType": "anything", "description": "", "definition": "random(1..4)", "name": "a", "group": "Ungrouped variables"}, "x1": {"templateType": "anything", "description": "", "definition": "random(-2..2 except 0)", "name": "x1", "group": "Ungrouped variables"}}, "name": "Even Functions", "preamble": {"css": "", "js": ""}, "parts": [{"mustBeReduced": false, "variableReplacements": [], "mustBeReducedPC": 0, "showCorrectAnswer": true, "correctAnswerStyle": "plain", "showFeedbackIcon": true, "notationStyles": ["plain", "en", "si-en"], "scripts": {}, "prompt": "If the \\(x\\) coordinate of the point \\(A\\) is \\(\\var{x1}\\) then what is the \\(x\\)-coordinate of the point \\(B\\)?
", "variableReplacementStrategy": "originalfirst", "type": "numberentry", "customMarkingAlgorithm": "", "marks": 1, "allowFractions": false, "unitTests": [], "correctAnswerFraction": false, "extendBaseMarkingAlgorithm": true, "maxValue": "-1*{x1}", "minValue": "-1*{x1}"}, {"mustBeReduced": false, "variableReplacements": [], "mustBeReducedPC": 0, "showCorrectAnswer": true, "correctAnswerStyle": "plain", "showFeedbackIcon": true, "notationStyles": ["plain", "en", "si-en"], "scripts": {}, "prompt": "If the \\(y\\) coordinate of the point \\(A\\) is \\(\\var{a*x1^2}\\) then what is the \\(y\\)-coordinate of the point \\(B\\)?
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