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tags:
- Mathematics
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An extremum (or extreme value in form of maximum and minimum values) of a given function is a point at which it attains a maximum or minimum value. Extrema are important because they provide a lot of information about a function and aid in answering questions of optimality.

**Local extremum**

A local extremum (or relative extremum) of a function is the point at which a maximum or minimum value of the function in some open interval containing the point is obtained.

**absolute extremum**

An absolute extremum (or global extremum) of a function in a given interval is the point at which a maximum or minimum value of the function is obtained.

A local minimum of function

Interactive Graph

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