Rational function

The rational function $y=\frac{x^2-3x-2}{x^2-4}$. The dotted lines are the asymptotes.

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. $f(x)=\frac{x}{x-3}$ is a rational function.

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

References

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