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Hard Square Root Problem

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Hard Square Root Problem

by gokoli » Sat Aug 13, 2011 3:38 pm
If x<0, then root(-x [x])

(the brackets are supposed to represent absolute value symbol for the second x. Both are the "-x" and second "x" are under the root symbol.)

a. -x
b. -1
c. 1
d. x
e. Square Root Symbol x

OA: A

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by sumgb » Sun Aug 14, 2011 6:35 am
First, x < 0

root(-x * |x|) = root ( x^2), Now,
root( x^2) = x if x >= 0 OR
root( x^2) = -x if x < 0
Since, it is given x < 0, answer must be -x

choice A

hope this helps...
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