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Add two algebraic fractions. Part of HELM Book 1.4.3.

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Express $\\displaystyle{\\frac{\\var{q2c[0]}}{\\var{latex(q2v[0])}}+\\frac{\\var{q2c[1]}}{\\var{latex(q2v[1])}}}$ as a single fraction.

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The simplest expression which has $\\var{latex(q2v[0])}$ and $\\var{latex(q2v[1])}$ as its factors is $\\var{latex(q2v[0])}\\var{latex(q2v[1])}$. This is the lowest common denominator. Both fractions are written using this common denominator. Noting that

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$\\displaystyle{\\frac{\\var{q2c[0]}}{\\var{latex(q2v[0])}}= \\frac{\\var{q2c[0]}\\var{latex(q2v[1])}}{\\var{latex(q2v[0])}\\var{latex(q2v[1])}} }$ and that $\\displaystyle{\\frac{\\var{q2c[1]}}{\\var{latex(q2v[1])}}= \\frac{\\var{q2c[1]}\\var{latex(q2v[0])}}{\\var{latex(q2v[1])}\\var{latex(q2v[0])}} }$ we find

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\\[\\frac{\\var{q2c[0]}}{\\var{latex(q2v[0])}}+\\frac{\\var{q2c[1]}}{\\var{latex(q2v[1])}}= \\frac{\\var{q2c[0]}\\var{latex(q2v[1])}}{\\var{latex(q2v[0])}\\var{latex(q2v[1])}}+\\frac{\\var{q2c[1]}\\var{latex(q2v[0])}}{\\var{latex(q2v[1])}\\var{latex(q2v[0])}} = \\var{q2ans}\\]

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No cancellation is now possible because neither $\\var{latex(q2v[0])}$ nor $\\var{latex(q2v[1])}$ is a factor in the numerator.

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