Find the range of the function f(x)=\acx2x2+1f(x) = \ac{x^2}{x^2 + 1}f(x)=\acx2x2+1.
[0,1)[0, 1)[0,1)
(0,1)(0, 1)(0,1)
[0,1][0, 1][0,1]
All real numbers