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(3^2)^0.5 = ...

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(3^2)^0.5 = ...

by Fractal » Sat Jul 16, 2011 5:26 am
could it be 3 as well as (-3) according to GMAT?

4^0.5 can only equal to 2 according to GMAT, right?

thx,
fractal
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by Ian Stewart » Sat Jul 16, 2011 7:56 am
I don't think I have ever seen a decimal exponent in an official GMAT question (though I have seen fractional exponents), but yes, if you see 4^0.5, or 4^(1/2), that is equal to 2, and not to -2. You can interpret the power of 1/2 to be the equivalent of a radical sign; that is, it gives you the non-negative square root. It's not the kind of technicality you'll need to worry about on the actual test, however.
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by Fractal » Fri Jul 22, 2011 8:11 am
Ian Stewart wrote:I don't think I have ever seen a decimal exponent in an official GMAT question (though I have seen fractional exponents), but yes, if you see 4^0.5, or 4^(1/2), that is equal to 2, and not to -2. You can interpret the power of 1/2 to be the equivalent of a radical sign; that is, it gives you the non-negative square root. It's not the kind of technicality you'll need to worry about on the actual test, however.
Thx, but just to be sure:

(3^2)^0.5 could be positive or negative?
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by MBA.Aspirant » Fri Jul 22, 2011 8:16 am
(3^2)^0.5 = √9 = 3
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by Fractal » Fri Jul 22, 2011 8:33 am
MBA.Aspirant wrote:(3^2)^0.5 = √9 = 3
but (x^2)^0.5 = x or -x
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