Contact The Learning Centre

# Rational expressions

### Definitions

Rational functions are of the form $f(x) = \frac{P_{n}(x)}{Q_{m}(x)}$ where $$P_{n} (x)$$ and $$Q_{m} (x)$$ are polynomial functions of the order $$n$$ and $$m$$ respectively, and $$Q$$ is not the zero function (the function whose output is always zero). For example, simple rational functions are: $f(x) = \frac{x+1}{2x^{2}-3x+1}$ or $f(x)= \frac{x+1}{x-2}$