Rational function

Rational function $y={\frac {x^{2}-3x-2}{x^{2}-4}}$

The curve gets closer and closer to touching the asymptote (the red line) but never does.

A rational function is a polynomial divided by a polynomial. f(x) = x/x − 3 is a rational function.

An asymptote is a line that a curve gets closer and closer to touching but never does.