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

1 Answer
Feb 15, 2018

Vertical asymptote: At x=1,-2

Horizontal asymptote: At y=0

X-intercept: None

Y-intercept: At y=1

Holes: None

Explanation:

To find the holes and vertical asymptotes, we first study the denominator.

We have x^2+x-2 in the denominator. Factorizing this will give us the vertical asymptotes.

x^2+x-2

x^2+2x-x-2

x(x+2)-1(x+2)

(x+2)(x-1)

The asymptotes are found when the answer is 0.

So,

(x+2)(x-1)=0

x=1,-2

There are vertical aymptotes at x=1,-2.

To find the horizontal asymptotes, we must look at the degree of the numerator (n) and the denominator (m).

If n>m, there is no horizontal asymptote

If n=m, we divide the leading coefficients,

If n<m, the asymptote is at y=0.

Here, n=0 and m=2, so the horizontal asymptote is at y=0.

Therefore, there is no x-intercept.

The y-intercept is found by taking all x to be equal to 0.

Doing so,

-2/(0^2+0-2)

-2/-2

-(-1)

1

The y-intercept is at y=1

There are no holes.