NandishSS wrote:
Bunuel wrote:
If \(x\) and \(y\) are negative numbers, what is the value of \(\frac{\sqrt{x^2}}{x}-\sqrt{-y*|y|}\)?
A. \(1+y\)
B. \(1-y\)
C. \(-1-y\)
D. \(y-1\)
E. \(x-y\)
HI
GMATGuruNY,
MentorTutoringCan you help me with this problem?
Consider x=-2 & y= -3
\(\frac{\sqrt{x^2}}{x}-\sqrt{-y*|y|}\) ==> \(\frac{\sqrt{-2^2}}{-2}-\sqrt{-(-3)*|-3|}\)
= -1-3 ==> -4
Only option D is valid. Am'I right?
Yes, and -2 and -3 are some of my go-to numbers for such complicated looking problems, since the two, when squared or cubed, will not often lead to multiple valid answer choices when you substitute for the variables there. You might say you read my mind. I see that
GMATGuruNY beat me to the parentheses tip. Make sure you understand the difference between the following:
\(-2^2=-4\)
and
\((-2)^2=4\)
It has to do with the order of operations, and the former is telling you to take 2, square it, and make the result negative. Although you still got the answer correct in this case, you might not in another such question, one in which the number needed to be negative.
Well done. Thank you for tagging me, and good luck with your studies.
- Andrew