How do you find the asymptotes for f(x)= (x^2 + 1) / (x - 2x^2)?

2 Answers
Jun 18, 2016

You look for extreme values taken by f

Explanation:

For large x, only the largest powers remain, and f approaches x^2/-2x^2 = -1/2 There is a pole at x - 2x^2 = 0 or x=1/2

Jun 18, 2016

vertical asymptotes x = 0 , x=1/2
horizontal asymptote y=-1/2

Explanation:

Vertical asymptotes occur as the denominator of a rational function tends to zero. To find the equation/s set the denominator equal to zero.

solve: x-2x^2=0rArrx(1-2x)=0rArrx=0,x=1/2

rArrx=0,x=1/2" are the asymptotes"

Horizontal asymptotes occur as

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

divide terms on numerator/denominator by x^2

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

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

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