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    According to my textbook,  \sqrt{72} = 6 \sqrt{2}.

    Why does it not also equal  3 \sqrt{8} ?
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    (Original post by Illidan2)
    According to my textbook,  \sqrt{72} = 6 \sqrt{2}.

    Why does it not also equal  3 \sqrt{8} ?
    It's the same thing. You can simplify your answer further to get the one in the textbook. Can you see how?
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    No, I do not see how. I notice 2 is the cube root of 8, but that is pretty much it. Because 8 is three times 2, can I just add 3 to the multiplier?
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    (Original post by Illidan2)
    No, I do not see how.
    Write 8=4 \times 2
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     8 = 4 \times 2
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    (Original post by Illidan2)
     8 = 4 x 2
    Well I kinda implied that then you get \sqrt{4 \times 2} in there and surely you know how this simplifies further.
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    (Original post by RDKGames)
    Well I kinda implied that then you get \sqrt{4 \times 2} in there and surely you know how this simplifies further.
     2 \sqrt{2}
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    (Original post by Illidan2)
     2 \sqrt{2}
    Yeah \sqrt{8}=2\sqrt{2} so then can you see how this leads your answer to their form?
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    Yeah. Because I have 3 lots of  \sqrt{8}, so I have three lots of  2 \sqrt 2 ! :3
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    Therefore  2 \times 3= 6 \sqrt{2}
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    Thank you!
 
 
 
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