How do you find the vertical, horizontal and slant asymptotes of: f(x)=(x + 1 )/ ( 2x - 4)?

1 Answer
Sep 10, 2016

vertical asymptote at x = 2
horizontal asymptote at y=1/2

Explanation:

The denominator of f(x) cannot be zero as this would make f(x) undefined. Equating the denominator to zero and solving gives the value that x cannot be and if the numerator is non-zero for this value then it is a vertical asymptote.

solve: 2x-4=0rArrx=2" is the asymptote"

Horizontal asymptotes occur as

lim_(xto+-oo),f(x)toc" (a constant)"

divide terms on numerator/denominator by x

f(x)=(x/x+1/x)/((2x)/x-4/x)=(1+1/x)/(2-4/x)

as xto+-oo,f(x)to(1+0)/(2-0)

rArry=1/2" is the asymptote"

Slant asymptotes occur when the degree of the numerator > degree of the denominator. This is not the case here ( both of degree 1 ) Hence there are no slant asymptotes.
graph{(x+1)/(2x-4) [-10, 10, -5, 5]}