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Function question

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Function question

by metallicafan » Tue Jul 23, 2013 8:43 am
Please, help me to understand this statement:

"For each value of y greater than 2*(3)^(1/2), the function f(x) is such that the equation f(x) = y has the form x = (y^2 + 12)/y

My interpretation is that the result of that function is 'y' and that the value of 'y' will depend on that equation. But 'y' must be greater than 2*(3)^(1/2).

Am I right?, please your comments.
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by [email protected] » Tue Jul 23, 2013 12:39 pm
Hi metallicafan,

Yes, you have interpreted this correctly.

As an aside though, this is far too complex for a typical GMAT function question. While you'll likely see one function question on Test Day, it's not going to look like this.

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by Matt@VeritasPrep » Tue Jul 23, 2013 4:44 pm
Yup, you've got it right: if y is greater than 2√3, then x = y + 12/y and f(x) = y. At that point you'd probably be asked which of the five answers could define the function, or something like that.

I don't think this is too hard for the GMAT - I had two function questions on the real exam that were at least as hard as this, though in different ways - but I think it'd be about 80th percentile in math, and perhaps not really their style.
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