# Extremum

## Extremum

Term that refers to either the maximum or the minimum of a function.

### Examples

• The function defined by the relationship y = x – 3 does not have a maximum or a minimum.
• The function defined by the relationship y = 2 has an extremum of 2.

• A second-degree polynomial function defined by f(x) = A$${x}^{2}$$+ Bx + C has a minimum if A > 0 and a maximum if A < 0.