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    (Original post by Kevin De Bruyne)
    1. What did you think of the help provided to your previous surds question? Did you complete it in the end? Is there anything you can learn from it?

    2. Your question seems to be missing the surds.

    3. Where is your attempt at this question? It is fine to be completely stumped but to say nothing at all with no working is not.
    I did complete it in the end, I did try the question but I don't understand how they got 12/3 / = sign for surd...
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    (Original post by RDKGames)
    Er... not sure what that thing is supposed to mean... please make it clearer!
    / = the surd sign because I don't know how to it and the 2 means squared.
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    (Original post by SBizzy)
    / = the surd sign because I don't know how to it and the 2 means squared.
    OK, so the first thing I'd do is notice that \sqrt{12} can be simplified to something in the form a\sqrt{3}

    Then expand the square and you should end up with 12 root 3 in the expression.
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    (Original post by RDKGames)
    OK, so the first thing I'd do is notice that \sqrt{12} can be simplified to something in the form a\sqrt{3}

    Then expand the square and you should end up with 12 root 3 in the expression.
    Would 12 root 3 be simplified into 4/3

    How is the 21- 12/3? That's what I don't know, I understand why we get 21 but not 12 root 3...
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    (Original post by SBizzy)
    Would 12 root 3 be simplified into 4/3
    Yes
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    (Original post by RDKGames)
    Yes

    How is the 21- 12/3? That's what I don't know, I understand why we get 21 but not 12 root 3...
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    (Original post by SBizzy)
    How is the 21- 12/3? That's what I don't know, I understand why we get 21 but not 12 root 3...
    Did you edit your last post...?

    Anyway, look, start over, \sqrt{12}=2\sqrt{3} so your question becomes (3-2\sqrt{3})^2=(3-2\sqrt{3})(3-2\sqrt{3})

    So then expanding it you have 9+4(3) which gives you your 21 but there are leftover surds (which I've missed out on purpose) with \sqrt{3}!

    Just show your expansion if you can't get it so I can point out where you're wrong.
 
 
 
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