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maths c1 - surds. lol (i'm failure)

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    11¬72/5¬32

    ¬ = square root

    Well, this question should be fairly straightforward, but I keep getting the answer (33¬2)/10

    I checked with a calculator and it told me the answer was 33/10

    I feel like I'm going mad with some of these questions

    Can someone please point out where I've gone wrong??
    That root 2 shouldn't be in my answer

    Thank you.
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    (Original post by ZiggyStarDust_)
    11¬72/5¬32

    ¬ = square root

    Well, this question should be fairly straightforward, but I keep getting the answer (33¬2)/10

    I checked with a calculator and it told me the answer was 33/10

    I feel like I'm going mad with some of these questions

    Can someone please point out where I've gone wrong??
    That root 2 shouldn't be in my answer

    Thank you.
    Just simplify them!

    11\sqrt{72}=11\sqrt{2}\sqrt{36}=  66\sqrt{2}

    5\sqrt{32}=5\sqrt{2}\sqrt{16}=20  \sqrt{2}
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    (Original post by ZiggyStarDust_)
    11¬72/5¬32

    ¬ = square root

    Well, this question should be fairly straightforward, but I keep getting the answer (33¬2)/10

    I checked with a calculator and it told me the answer was 33/10

    I feel like I'm going mad with some of these questions

    Can someone please point out where I've gone wrong??
    That root 2 shouldn't be in my answer

    Thank you.
    Note that \sqrt{72} = \sqrt{36 \times 2} = \sqrt{36}\sqrt{2} = 6\sqrt{2} and \sqrt{32} = \sqrt{16 \times 2} = \sqrt{16}\sqrt{2} = 4\sqrt{2} so your fractions is

    \displaystyle 

\begin{equation*}\frac{11 \times 6\sqrt{2}}{5 \times 4\sqrt{2}} = \frac{11\times 6}{5\times 4} \times \underbrace{\frac{\sqrt{2}}{ \sqrt{2} }}_{=1} \end{equation*}
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    (Original post by RDKGames)
    Just simplify them!

    11\sqrt{72}=11\sqrt{2}\sqrt{36}=  66\sqrt{2}

    5\sqrt{32}=5\sqrt{2}\sqrt{16}=20  \sqrt{2}
    OH MY GOD IT'S THAT SIMPLE



    I feel like such an idiot now. Completely. Cannot believe I didn't think to do this IN THE FIRST PLACE.

    Emotions are running high, i'm sorry.
    Anyway, Thank you very much for this.
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    (Original post by Zacken)
    Note that \sqrt{72} = \sqrt{36 \times 2} = \sqrt{36}\sqrt{2} = 6\sqrt{2} and \sqrt{32} = \sqrt{16 \times 2} = \sqrt{16}\sqrt{2} = 4\sqrt{2} so your fractions is

    \displaystyle 

\begin{equation*}\frac{11 \times 6\sqrt{2}}{5 \times 4\sqrt{2}} = \frac{11\times 6}{5\times 4} \times \underbrace{\frac{\sqrt{2}}{ \sqrt{2} }}_{=1} \end{equation*}
    thank you very much for this!
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    (Original post by ZiggyStarDust_)
    thank you very much for this!
    No problem.
 
 
 
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