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\({x}^{2}\)+ B*x*+ C has a minimum if A > 0 and a maximum if A < 0.