Answer:
f(x) = 2x / (x - 1)
Step-by-step explanation:
One such function would be:
2x
f(x) = -----------
x - 1
f(x) is undefined at x = 1, so has a vertical asymptote at x = 1.
As x increases without bound, f(x) approaches (2x) / (x), or just 2. Thus, f(x) has the horiz. asy. y = 2.