Find the range of the function f(x)=3−2x−1f(x) = 3 - 2^{x-1}f(x)=3−2x−1.
(0,∞)(0, \infty)(0,∞)
(−∞,3)(-\infty, 3)(−∞,3)
(3,∞)(3, \infty)(3,∞)
(−∞,∞)(-\infty, \infty)(−∞,∞)