Stupid question on even roots

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by neelgandham » Fri Jan 20, 2012 4:58 pm
Yes, it always yields a positive value. Let me showcase it with an example.
4√16 = √4 or √-4(which is a complex number and can be ignored) = 2 (The principal root).
In GMAT, one must consider the principal square root and hence a positive value.

Why ?
I will leave that for the Experts to answer it.

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by Anurag@Gurome » Fri Jan 20, 2012 8:16 pm
neelgandham wrote:Yes, it always yields a positive value. Let me showcase it with an example.
4√16 = √4 or √-4(which is a complex number and can be ignored) = 2 (The principal root).
In GMAT, one must consider the principal square root and hence a positive value.

Why ?
I will leave that for the Experts to answer it.

Experts : Please correct me if I am wrong!
That's absolutely correct. The square root refers to only positive square root.
We can say that √(x²) = |x|
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by ame » Sat Jan 21, 2012 3:07 am
even root of real number is written in form
x^(1/2n) where is a set of positive integer.
so, (X^(1/2))^(1/n) is defined when xis real positive value.
then the result must be a positive value.