If x^3 * y^6 * z^9 < 0, which of the following must be true?
I. xy < 0
II. yz < 0
III. xz < 0
a) I only
b) II only
c) III only
d) I and II only
e) I and III only
5-Day Free Trial
5-day free, full-access trial TTP
Available with Beat the GMAT members only code
MORE DETAILS
If x^3 * y^6 * z^9 < 0, which of the following must be tr
This topic has expert replies
-
kbharadwaj.1987
- Senior | Next Rank: 100 Posts
- Posts: 85
- Joined: Fri Jul 24, 2009 4:05 pm
-
PussInBoots
- Master | Next Rank: 500 Posts
- Posts: 157
- Joined: Tue Oct 07, 2008 5:47 am
- Thanked: 3 times
x^3 * y^6 * z^9 < 0
(x * y^2 * z^3)^3 < 0
x * y^2 * z^3 < 0
x * z^3 < 0 (y^2 is non-negative)
x * z * z^2 < 0
xz <0
y could be whatever. As long as it's not zero, y^6 will be positive
(x * y^2 * z^3)^3 < 0
x * y^2 * z^3 < 0
x * z^3 < 0 (y^2 is non-negative)
x * z * z^2 < 0
xz <0
y could be whatever. As long as it's not zero, y^6 will be positive
-
kbharadwaj.1987
- Senior | Next Rank: 100 Posts
- Posts: 85
- Joined: Fri Jul 24, 2009 4:05 pm
