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I'm sorry. I feel dumb for not remembering how to do this but I'm helping my girlfriend with some math stuff and I'm forgetting how to simplify this expression.

$$\sqrt 3 - 27$$

I think that you are suppose to multiply or divide it by something so we can get rid of the sqrt but I'm stumped on how to accomplish that. Thanks in advance.

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closed as unclear what you're asking by Qwerty, E. Joseph, астон вілла олоф мэллбэрг, zhoraster, John B Nov 30 '16 at 10:28

Please clarify your specific problem or add additional details to highlight exactly what you need. As it's currently written, it’s hard to tell exactly what you're asking. See the How to Ask page for help clarifying this question. If this question can be reworded to fit the rules in the help center, please edit the question.

  • $\begingroup$ There's nothing left to do to simplify the expression any further. $\endgroup$ – 5xum Nov 30 '16 at 7:08
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    $\begingroup$ If you had something like $\dfrac{a}{\sqrt{3}-27}$, you might rationalize the denominator by multiplying top-and-bottom by the conjugate $\sqrt{3}+27$. However, the expression $\sqrt{3}-27$ alone is fine. $\endgroup$ – Corellian Nov 30 '16 at 7:12
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    $\begingroup$ @Qwerty It's an honest question asked in good faith, with a specific problem and an attempt at solving it. Why should it not have an upvote? $\endgroup$ – Patrick Stevens Nov 30 '16 at 7:13
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    $\begingroup$ @PatrickStevens When I hover my mose over the upvote sign , it says shows research effort , and is useful. Does this question really satisfy these two? $\endgroup$ – Qwerty Nov 30 '16 at 7:18
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    $\begingroup$ Any chance that you've misspelled your girlfriend's question from $\sqrt[3]{-27}$ into $\sqrt{3}-27$? $\endgroup$ – barak manos Nov 30 '16 at 7:42
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Many people already pointed out that your expression can't really get much more neater than that. One can, however, do the following:

$$27 = 3^3 \Rightarrow 27 = {\sqrt 3}^6,\\ \sqrt 3 - 27 = \sqrt 3 - {\sqrt 3}^6 = \sqrt 3 (1 - {\sqrt 3}^5) = \sqrt 3 (1 - 9\sqrt 3)$$

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    $\begingroup$ This answer stretches the definition of 'simplify' a little. $\endgroup$ – user259242 Nov 30 '16 at 8:37
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    $\begingroup$ @user259242 sure it does, but apart from this, and assuming we must do something, everything else will be more complicated than this. $\endgroup$ – RGS Nov 30 '16 at 8:38

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