GMAT Prep question

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GMAT Prep question

by rossmj » Fri Apr 17, 2009 7:26 am
If x does not equal 0, then sqrt(x^2)/x=
A -1
B 0
C 1
D x
E lxl/x

I was under the impression that imaginary numbers were not tested on the GMAT and immediately ruled out x being negative because it was inside a sqrt.
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by deepoe » Fri Apr 17, 2009 8:15 am
It's C or not?

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by rossmj » Fri Apr 17, 2009 8:22 am
No E thus my confusion over the possibility of x being negative inside a square root

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by deepoe » Fri Apr 17, 2009 9:01 am
| X | means that -x = x

So it is possible but I can't give a clear explanation :$

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by gmat740 » Fri Apr 17, 2009 10:29 am
sq-rt(4) = +2 and -2

so,
sq-rt(2^2) = +2 and -2

so,

sqrt(x^20 )= +x and -x = |x|

Hope this helps

Karan

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by dumb.doofus » Fri Apr 17, 2009 9:35 pm
IMO E, if x is not negative.. other choices can be eliminated..
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we are given no information about x, other than it is not equal to zero. therefore, x can be positive OR negative. choice E deals with both possibilities in the absolute value of x.

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by ketkoag » Mon Apr 20, 2009 10:13 am
E for me as well..

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Re: GMAT Prep question

by dabral » Mon Apr 20, 2009 1:33 pm
Here is my video explanation for this problem. This is all work in progress as I slowly assemble all the solutions to GMATPrep questions.

https://www.gmatquantum.com/shared-posts ... tic10.html
rossmj wrote:If x does not equal 0, then sqrt(x^2)/x=
A -1
B 0
C 1
D x
E lxl/x

I was under the impression that imaginary numbers were not tested on the GMAT and immediately ruled out x being negative because it was inside a sqrt.