Ans = -x


This is a positive\negative question. So GMAT will trick you with positive and negatives.

Now we know that x < 0 ....that means -x >0 .....e.g. -1 , -2 and so on

|x| is the absolute value of x = positive value of x
-x is also the positive value of x

Thus -x|x| gives us x ^2 ...which is positive

we take the sqrt of -x|x| and we get back x .....WRONG

we dont get x back ...we get -x back because sqrt gave us back the positive version of x ..which was -x

Thus that should be the answer

suppose x=-1
then -x*lxl=-(-1)*l-1l=1*1=1
we assumed x=-1 and we are getting value 1 which is nothing but -x(bcoz x is -1)
hence value for the expression is -x

Thanks guyz...

neerajkumar1_1 wrote:if x<0, then sqrt(-x*|x|) is ?

since x<0 so |x| = -x
--> sqrt(-x*|x|) = sqrt(-x*-x) = sqrt(x2) = |x| = -x (since x<0)