GMAT Prep Question help needed : Tomo is my exam

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by Frankenstein » Wed Jun 01, 2011 3:54 am
Hi,
Square root of a number is always the positive root. If x<0, |x|1=-x
sqrt(-x|x|) = sqrt(-x.-x) = sqrt(x^2) = |x| = -x
Hence, A
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by Anahatha » Wed Jun 01, 2011 4:01 am
Thanks a ton for the quick reply. I arrived till the fnal step of getting |x| . |x| can be x or -x. Since the question specifically mentions that x is negative we choose -x. Is my reasoning correct or is there someother way to it ?

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by Frankenstein » Wed Jun 01, 2011 4:04 am
Anahatha wrote:Thanks a ton for the quick reply. I arrived till the fnal step of getting |x| . |x| can be x or -x. Since the question specifically mentions that x is negative we choose -x. Is my reasoning correct or is there someother way to it ?
Hi,
Yes.. Your logic is correct.
Good luck for your test!
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by Anahatha » Wed Jun 01, 2011 4:13 am
Thanks