Sqroots

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Sqroots

by Lookingfor700GMAT » Wed Mar 10, 2010 9:19 am
If x < 0 then square root of -x|x|

is -x,-1,1,x or square root of x. I chose X but it is - x

Isn't - (a negative number) a positive number then you times it with x so x multiplied by x is x^2 which is x after being square rooted?
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by Osirus@VeritasPrep » Wed Mar 10, 2010 10:22 am
it can't be negative x. What is the source. if you have a negative number and you put a negative sign with that number it becomes pos. I think the book may have made a mistake.
https://www.beatthegmat.com/the-retake-o ... 51414.html

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by Lookingfor700GMAT » Wed Mar 10, 2010 10:40 am
Do you make the answer x?

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by Lookingfor700GMAT » Wed Mar 10, 2010 10:41 am
It was on GMAT Prep 2

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by Osirus@VeritasPrep » Wed Mar 10, 2010 10:46 am
The only way for it to be negative x is if the stimulus reads

- sqrt( -x|x|) Otherwise, there is no way to get a negative number from a square root, because a negative number within a square root is imaginary and imaginary numbers aren't on the GMAT.
https://www.beatthegmat.com/the-retake-o ... 51414.html

Brandon Dorsey
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