If f(x)=1x2f(x) = \frac{1}{x^2}f(x)=x21, what is the range of f(x)f(x)f(x) for x≠0x \neq 0x=0?
(0,∞)(0, \infty)(0,∞)
All real numbers
[1,∞)[1, \infty)[1,∞)
[0,∞)[0, \infty)[0,∞)