knight247 wrote:Thanks Geva...And there definitely is problem with this question...But just for the sake of improving my math knowledge, can u please provide an explanation for statement 2. Thanks
Begin with an easy plug in for A and B. 1/3 is smaller than 1/2, right? So let A=3 and B=2, so that 1/A is indeed smaller than 1/B. What does that do to the question stem, given a negative x (for example x=-2?)
3^-2 = 1/3^2 = 1/9
2^-2 = 1/2^2 = 1/4
Since 1/9 is smaller than 1/4, this means that A^x is NOT greater than B^x, so the answer is NO.
Fine, now can we fine a Yes, where A^x IS greater than B^x?
a negative A and positive B will assure that 1/a is smaller than 1/b, since negative is smaller than positive. But if we keep x as -2, the even power will return A^x back to the positive side.
B=2
A=-1
1/A is smaller than 1/B, since 1/-1 < 1/2
Go to the question stem, keeping X=-2:
A^x = (-1)^-2 = 1
B^x = 2^-2 = 1/2^2 = 1/4.
1 is greater than 1/4, so here A^x is greater than B^x and the answer is "Yes".
Since stat. (2) allows both a yes and a no answer, it is insufficient.