-
shri_ankur
- Junior | Next Rank: 30 Posts
- Posts: 10
- Joined: Tue Oct 02, 2007 7:13 pm
I think it's A, -x.
Since x is negative, -x is positive and -x = |x|.
Therefore, -x*|x| = (|x|)^2. Then, plugging this into the original problem,
sqrt((|x|^2)) = |x| = -x
You could solve this by plugging in a negative number and seeing what you get. For instance, say you chose -4 to be x. Then,
sqrt(-x*|x|) = sqrt(-(-4)*|-4|) = sqrt(4*4) = sqrt(16) = 4 = -x
