How do you graph #f(x)=(-x-1)/(x+2)# using holes, vertical and horizontal asymptotes, x and y intercepts?

1 Answer
Mar 16, 2017

see explanation.

Explanation:

#color(blue)"Asymptotes"#

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+2=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)/(x/x+2/x)=(-1-1/x)/(1+2/x)#

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

#rArry=-1" is the asymptote"#

Holes occur if there is a duplicate factor on the numerator/denominator. This is not the case here hence there are no holes.

#color(blue)"Intercepts"#

#x=0toy=-1/2rArr(0,-1/2)larr"y-intercept"#

#y=0to-x-1=0tox=-1rArr(-1,0)#
graph{(-x-1)/(x+2) [-10, 10, -5, 5]}