Determine the range of f(x)=exex+1f(x) = \frac{e^x}{e^x + 1}f(x)=ex+1ex.
(0,1)(0, 1)(0,1)
[0,1][0, 1][0,1]
(−∞,∞)(-\infty, \infty)(−∞,∞)
(1,∞)(1, \infty)(1,∞)