How do you identify all asymptotes for f(x)=-(x+2)/(x+4)f(x)=x+2x+4?

1 Answer
Jul 17, 2017

"vertical asymptote at " x=-4vertical asymptote at x=4
"horizontal asymptote at " y=-1horizontal asymptote at y=1

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 " x+4=0rArrx=-4" is the asymptote"solve x+4=0x=4 is the asymptote

"horizontal asymptotes occur as"horizontal asymptotes occur as

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

"divide terms on numerator/denominator by x"

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

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

rArry=-1" is the asymptote"
graph{-(x+2)/(x+4) [-10, 10, -5, 5]}