What is the range of f(x)=xx2+1f(x) = \frac{x}{x^2+1}f(x)=x2+1x?
[−1,1][-1, 1][−1,1]
[−0.5,0.5][-0.5, 0.5][−0.5,0.5]
(−∞,∞)(-\infty, \infty)(−∞,∞)
[0,1][0, 1][0,1]