// Numbas version: finer_feedback_settings {"name": "Anna's Expansion of two brackets: Linear 2 positive coefficients - test", "extensions": [], "custom_part_types": [], "resources": [], "navigation": {"allowregen": true, "showfrontpage": false, "preventleave": false, "typeendtoleave": false}, "question_groups": [{"pickingStrategy": "all-ordered", "questions": [{"parts": [{"variableReplacementStrategy": "originalfirst", "stepsPenalty": "0", "customMarkingAlgorithm": "", "marks": 0, "type": "gapfill", "sortAnswers": false, "useCustomName": false, "gaps": [{"showPreview": true, "customMarkingAlgorithm": "", "maxlength": {"partialCredit": 0, "message": "
Input your answer as a quadratic in $x$, in the form $ax^2+bx+c$ for appropriate integers $a,\\;b,\\;c$.
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"}, "showFeedbackIcon": true, "vsetRangePoints": 5, "variableReplacementStrategy": "originalfirst", "checkingAccuracy": 0.001, "marks": 2, "type": "jme", "answerSimplification": "std", "variableReplacements": [], "checkingType": "absdiff", "failureRate": 1, "unitTests": [], "answer": "{a*c}x^2+{b*c+a*d}x+{b*d}", "checkVariableNames": false, "extendBaseMarkingAlgorithm": true}], "variableReplacements": [], "scripts": {}, "showCorrectAnswer": true, "customName": "", "steps": [{"variableReplacementStrategy": "originalfirst", "customMarkingAlgorithm": "", "marks": 0, "type": "information", "useCustomName": false, "variableReplacements": [], "scripts": {}, "showCorrectAnswer": true, "customName": "", "unitTests": [], "prompt": "There are many ways to expand an expression such as $(ax+b)(cx+d)$.
\nOne method is sometimes referred to as FOIL, a mnemonic to help us remember which terms to multiply with one another:
\nFirst $ax \\times cx$
\nOutside $ax \\times d$
\nInside $b \\times cx$
\nLast $b \\times d$
\nWe then add these together and simplify by collecting like terms.
", "showFeedbackIcon": true, "extendBaseMarkingAlgorithm": true}], "unitTests": [], "prompt": "$\\simplify[std]{({a}x+{b})({c}x+{d})}=\\;$[[0]].
\nYour answer should be a quadratic in $x$ and should not include any brackets.
\n", "showFeedbackIcon": true, "extendBaseMarkingAlgorithm": true}], "variable_groups": [], "functions": {}, "tags": [], "rulesets": {"std": ["all", "!noLeadingMinus", "!collectNumbers"]}, "advice": "There are many ways to expand an expression such as $(ax+b)(cx+d)$.
\nOne method is sometimes referred to as FOIL, a mnemonic to help us remember which terms to multiply with one another:
\nFirst $ax \\times cx$
\nOutside $ax \\times d$
\nInside $b \\times cx$
\nLast $b \\times d$
\nWe then add these together and simplify by collecting like terms.
\n\n\n\\[\\begin{eqnarray*}\\simplify[std]{ ({a}x+{b})({c}x+{d})}&=&(\\var{a}x\\times\\var{c}x)+(\\var{a}x\\times\\var{d})+(\\var{b}\\times\\var{c}x)+(\\var{b}\\times\\var{d})\\\\&=&(\\var{a*c}x^2)+(\\var{a*d}x)+(\\var{b*c}x)+(\\var{b*d})\\\\&=&\\simplify[std]{{a*c}x^2+{(a*d+b*c)}x+{b*d}}\\end{eqnarray*}\\]
\n", "statement": "
Expand the following to give a quadratic in $x$.
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\nrebelmaths
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