// Numbas version: exam_results_page_options {"name": "1.4.3.1 Add two algebraic fractions version 1", "extensions": [], "custom_part_types": [], "resources": [], "navigation": {"allowregen": true, "showfrontpage": false, "preventleave": false, "typeendtoleave": false}, "question_groups": [{"pickingStrategy": "all-ordered", "questions": [{"name": "1.4.3.1 Add two algebraic fractions version 1", "tags": [], "metadata": {"description": "

Simplify ax/b +/- cx/d, where x is a randomised variable, and a,b,c,d are randomised integers.

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Simplify, if possible, $\\displaystyle{\\var{te[0]}\\var{sgnl}\\var{te[1]}}$

", "advice": "

Given $\\displaystyle{\\var{te[0]}\\var{sgnl}\\var{te[1]}}$

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$\\displaystyle{\\var{te[0]}}$ can be simplified to $\\displaystyle{\\var{te_red[0]}}$

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$\\displaystyle{\\var{te[1]}}$ can be simplified to $\\displaystyle{\\var{te_red[1]}}$

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so $\\displaystyle{\\var{te[0]}\\var{sgnl}\\var{te[1]} = \\var{te_red[0]} \\var{sgnl} \\var{te_red[1]}}$

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The terms have a common factor of $\\var{ve}$.

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So $\\displaystyle{\\var{te_red[0]}\\var{sgnl}\\var{te_red[1]} = \\var{ve}\\left(\\var{fre[0]}\\var{sgnl}\\var{fre[1]} \\right)  }$

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The lowest common multiple of $\\var{den_red[0]}$ and $\\var{den_red[1]}$ is $\\var{lcm}$.

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So: \\[\\begin{align*}\\var{te_red[0]} \\var{sgnl} \\var{te_red[1]} &= \\var{ve} \\left( \\frac{\\var{mult[0]}}{\\var{mult[0]}}\\times\\var{fre[0]} \\var{sgnl} \\frac{\\var{mult[1]}}{\\var{mult[1]}}\\times \\var{fre[1]}\\right)\\\\&=\\var{ve}\\left(\\frac{\\var{mult[0]}\\times\\var{num_red[0]} \\var{sgnl} \\var{mult[1]}\\times\\var{num_red[1]}}{\\var{lcm}}\\right)\\\\&=\\var{ans}\\end{align*}\\]

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list of possible denominators

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The numerators

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The two tems as reduced expressions. Used in the advice.

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the final answer

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The fractions without the variable

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lowest common multiple of the reduced denominators

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What each term needs to be multipled by to put it over a common fraction. Used in the advice display.

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the denominators of the reduced fractions

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for display in the advice

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the fractions as strings, for display

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display version of the sign.

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