How do you find the asymptotes for f(x) =(x^2 - 16)/(x^2- 5x + 4)?

1 Answer
Feb 14, 2016

Vertical asymptotes are x=1 and x=4 and horizontal asymptote is y=1

Explanation:

The vertical asymptotes are given by restrictions on the domain and hence come from the zeroes of the denominator.

Putting x^2-5x+4=0 ad solving this will give domain

x^2-5x+4=0 i.e. x^2-x-4x+4=0 or

x(x-1)-4(x-1)=0 or (x-1)(x-4)=0

i.e. x= 1 or 4

Hence x can take all values other than 1 and 4

and vertical asymptotes are x=1 and x=4.

Since, numerator and denominator of the function are of same degree, horizontal asymptote is found by dividing the leading terms

i.e. x^2/x^2 i.e. 1.

Hence horizontal asymptote is y=1