How do you find the vertical, horizontal or slant asymptotes for (2x^2+x-3)/(x^2-4)?

1 Answer
Jun 21, 2016

see below

Explanation:

for vertical asymptotes, look for when the denominator is zero. here that requires x^2 - 4 = 0 \implies x = pm 2

next, exploring x \to \pm \infty, we should note that (2x^2 + x - 3) / (x^2 - 4) = (2 + 1/x - 3\x^2) / (1 - 4/x^2) , obtained by dividing top and bottom by x^2

and it's not hard to see that [(2 + 1/x - 3\x^2) / (1 - 4/x^2) ]_{x \to pm \infty} = 2 which is a horizontal asymptote