How do you find the vertical, horizontal or slant asymptotes for f(x) = (8x-12)/( 4x-2)f(x)=8x124x2?

1 Answer
Feb 25, 2016

There is a horizontal asymptote y = 2y=2.

There is a vertical asymptote x = 1/2x=12.

Explanation:

This is the graph of f(x)f(x).

graph{(8x-12)/(4x-2) [-20, 20, -10, 10]}

First rewrite f(x)f(x) by simplifying it.

f(x) = frac{8x-12}{4x-2}f(x)=8x124x2

= 2-frac{4}{2x-1}=242x1

You can see that

lim_{x->oo} f(x) = lim_{x->oo} (2-frac{4}{2x-1})

= 2-0

= 2

Similarly,

lim_{x->-oo} f(x) = 2

There is a horizontal asymptote y = 2.

f(x) is undefined at x = 1/2.

There is a vertical asymptote x = 1/2.