How do you find the Vertical, Horizontal, and Oblique Asymptote given ((x-3)(9x+4))/(x^2-4)(x3)(9x+4)x24?

1 Answer
Jan 26, 2017

The vertical asymptotes are x=2x=2 and x=-2x=2
The horizontal asymptote is y=9y=9
No slant asymptote

Explanation:

Let f(x)=((x-3)(9x+4))/(x^2-4)f(x)=(x3)(9x+4)x24

Let's factorise the denominator

x^2-4=(x+2)(x-2)x24=(x+2)(x2)

As you cannot divide by 00, x!=2x2 and x!=-2x2

The vertical asymptotes are x=2x=2 and x=-2x=2

As the degree of the numerator is == the degree of the denominator, there is no slant asymptote

lim_(x->+-oo)f(x)=lim_(x->+-oo)(9x^2)/x^2=9

The horizontal asymptote is y=9

graph{(y-((x-3)(9x+4)/(x^2-4)))(y-9)=0 [-41.1, 41.1, -20.55, 20.57]}