On Thu, 1 May 2008 10:29:57 -0700 (PDT), henrysun909@[EMAIL PROTECTED]
wrote:
>Hello again.
>
>I am looking at the XAM practice book for the math CSET, which I hope
>to take in July. In it is the following problem:
>
>[6 + 2sqrt(3)] / [4 - sqrt(6)] (sorry if I have gotten the conventions
>wrong).
I don't see any problem stated, just an expression.
>When I solve this problem by multiplying numerator and denominator by
>the conjugate of [4 - sqrt(6)] = [4 + sqrt(6)], I get
>
>[6 + 2sqrt(3)] x [4 + sqrt(6)] / [4 - sqrt(6)] x [4 + sqrt(6)] =
>
>24 + 8sqrt(3) + 2sqrt(18) + 6sqrt(6) / 16 - 6 =
>24 + 8sqrt(3) + 6sqrt(2) + 6sqrt(6) / 10 =
>12 + 4sqrt(3) + 3sqrt(2) + 3sqrt(6) / 5 = 6.10386
>
If the problem was to rationalize the denominator than your answer is
correct.
>The book's answer is:
>
>-3sqrt(2) -9sqrt(3) -3sqrt(6) - 12 = -39.179
>
>Can someone confirm to me that the book's answer is wrong? Or, if the
>book's answer is right and I am wrong, can someone point out where I
>made my mistake?
>
Since you never stated what the problem was, it's hard to know for
sure...
--Lynn
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