by gokul_nair1984 Sat Sep 25, 2010 1:33 pm
Here you go:
If a and b are integers and a is not equal to b, is ab > 0?
(1) a^b > 0
(2) a^b is a non-zero integer
For Statement 1, substitute
Let a=2 and b=3...So 2^3=8, which is greater than 0. ab=6. Thus ab>0.
Let a=-2 and b=2..So (-2)^2=4, which is greater than 0. ab=-4.
Thus ab<0.
Hence A is insufficient.
You can substitute the same values for a and b to disprove B as well.
Combining both Statements, again use the same numbers
(infact, you don't need to do this) and you'll find C to be insufficient.
So E is the answer