himu wrote:If x > 0, does f(x^2) = f(x)^2 ?
(1)f(x)=√x
(2)x=9
Target question:
Does f(x^2) = f(x)^2 ?
Statement 1: f(x)=√x
Since we now know what the function looks like, the target question is now . . .
Does √(x^2) = (√x)^2 ?
The answer to this question is
YES.
If x
> 0, then √(x^2) definitely equals (√x)^2
Since we can answer the
target question with certainty, statement 1 is SUFFICIENT
Statement 2: x=9
Since we don't know anything about the function f, we cannot answer the
target question with certainty.
So statement 2 is NOT SUFFICIENT
Answer =
A
Cheers,
Brent
Brent Hanneson - Creator of GMATPrepNow.com
