Find the range of f(x)=\acx2−4x2+4f(x) = \ac{x^2 - 4}{x^2 + 4}f(x)=\acx2−4x2+4.
[−1,1)[-1, 1)[−1,1)
(−1,1)(-1, 1)(−1,1)
[0,1)[0, 1)[0,1)
All real numbers