Question

How do you graph `f(x) = (x^2 - 1) / (x+1)` on a coordinate graph?

Answer 1

You can factorise first, and then cancel.

Explanation:

`->f(x)=((x+1)(x-1))/(x+1)=(cancel((x+1))(x-1))/cancel(x+1)`

You're left with a simple linear function:
`f(x)=x-1`

BUT!!
There is a discontinuity at `x=-1`, as this would make the denominator of the original function `=0`.

But since `lim_(x->-1^-) f(x)=lim_(x->-1^+) f(x)=-2`

this discontinuity is considered removable.
graph{(x^2-1)/(x+1) [-10, 10, -5, 5]}