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Math Help - Exact value

  1. #1
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    Exact value

    How do I show sqrt(2/5) as an exact value?

    Thanks
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  2. #2
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    Quote Originally Posted by bigroo View Post
    How do I show sqrt(2/5) as an exact value?

    Thanks
    That is an exact value.

    \sqrt{\frac{2}{5}} = \frac{\sqrt2}{\sqrt5}

    You can rationalise the denominator by multiplying by \frac{\sqrt5}{\sqrt5}

    \frac{\sqrt2}{\sqrt5} \cdot \frac{\sqrt5}{\sqrt5} = \frac{\sqrt{10}}{5}

    Although it's no more exact than the original expression
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  3. #3
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    Thanks for your help, I just wasn't sure if I could express it differently.
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