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help with fractions + more low intelligence questions needing to be answered watch

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    why does

     \dfrac{\frac{a}{b}}{c} \not = \dfrac{ac}{b}???

    also does  \sqrt 50 = \pm 5\sqrt 2?
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    a/b x 1/c

    Remove the +- for the surds, apart from that its correct.
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    \frac{\frac{a}{b}}{c} = \frac{\frac{a}{b}}{\frac{c}{1}} = \frac{a}{b} * \frac{1}{c}  = \frac{a}{bc}

     \sqrt{50} = \sqrt{25*2} = \sqrt{25}*\sqrt{2} = 5\sqrt{2}

    Just the square root of a number usually means the positive square root.
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    (Original post by Math12345)
    \frac{\frac{a}{b}}{c} = \frac{\frac{a}{b}}{\frac{c}{1}} = \frac{a}{b} * \frac{1}{c}  = \frac{a}{bc}

     \sqrt{50} = \sqrt{25*2} = \sqrt{25}*\sqrt{2} = 5\sqrt{2}

    Just the square root of a number usually means the positive square root.
    (Original post by Vikingninja)
    a/b x 1/c

    Remove the +- for the surds, apart from that its correct.
    thanks both
 
 
 
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