// Numbas version: finer_feedback_settings {"name": "Combining algebraic fractions 0", "extensions": [], "custom_part_types": [], "resources": [], "navigation": {"allowregen": true, "showfrontpage": false, "preventleave": false, "typeendtoleave": false}, "question_groups": [{"pickingStrategy": "all-ordered", "questions": [{"functions": {}, "name": "Combining algebraic fractions 0", "tags": ["algebra", "algebraic fractions", "algebraic manipulation", "combining algebraic fractions", "common denominator"], "advice": "\n

We have:

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\\[\\simplify[std]{{a} + ({c} / ({a2}*x + {d})) = ({a} * ({a2}*x + {d}) + {c})  / (({a2}*x + {d})) = ({a*a2} * x + {a * d + c}) / ( ({a2}*x + {d}))}\\]

\n ", "rulesets": {"std": ["all", "!collectNumbers", "fractionNumbers", "!noLeadingMinus"]}, "parts": [{"stepspenalty": 1.0, "prompt": "

Express \\[\\simplify[std]{{a}     + ({c} / ({a2}x + {d}))}\\] as a single algebraic fraction.

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Input the fraction here: [[0]].

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Input your answer in the form $\\displaystyle \\frac{(ax+b)}{(cx+d)}$ with no other brackets than those shown.

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You can click on Show steps for help. You will lose 1 mark if you do so.

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Input as a single fraction.

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Input as a single fraction

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The formula for adding these expressions is :
\\[\\simplify[std]{a + {s1} * (c / d) = (ad + {s1} * bc) / d}\\]

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and for this exercise we have  $\\simplify{d={a2}x+{d}}$.

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\n ", "type": "information", "marks": 0.0}], "marks": 0.0, "type": "gapfill"}], "extensions": [], "statement": "\n

Add the following  together and express as a single algebraic fraction.

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\n ", "variable_groups": [], "progress": "ready", "type": "question", "variables": {"a": {"definition": "random(1..9)", "name": "a"}, "c": {"definition": "random(-9..9 except [0,-a*d])", "name": "c"}, "d": {"definition": "random(-9..9 except [0,a2])", "name": "d"}, "s1": {"definition": "if(c<0,-1,1)", "name": "s1"}, "a2": {"definition": "random(2..9)", "name": "a2"}, "nb": {"definition": "if(c<0,'taking away','adding')", "name": "nb"}}, "metadata": {"notes": "\n \t\t \t\t \t\t

5/08/2012:

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Added tags.

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Added description.

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Changed to two questions, for the numerator and denomimator, rather than one as difficult to trap student input for this example. Still some ambiguity however.

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12/08/2012:

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Back to one input of a fraction and trapped input in Forbidden Strings.

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Used the except feature of ranges to get non-degenerate examples.

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Checked calculation.OK.

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Improved display in content areas.

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Express $\\displaystyle a \\pm  \\frac{c}{x + d}$ as an algebraic single fraction.

", "licence": "Creative Commons Attribution 4.0 International"}, "showQuestionGroupNames": false, "question_groups": [{"name": "", "pickingStrategy": "all-ordered", "pickQuestions": 0, "questions": []}], "contributors": [{"name": "Bill Foster", "profile_url": "https://numbas.mathcentre.ac.uk/accounts/profile/6/"}]}]}], "contributors": [{"name": "Bill Foster", "profile_url": "https://numbas.mathcentre.ac.uk/accounts/profile/6/"}]}