The difference is that the two concepts are different. Compared with its two sides, the extreme value is the maximum when it is greater than the two sides, and the minimum when it is less than the two sides; The maximum value is the maximum and minimum value of the function within the defined domain or specified interval. Except for a specific function, the two are not necessarily related.

Connection: in some cases, the function has an extreme value and no maximum value; In other cases, the function has a maximum and no value, in other cases, maximum = extreme value.

Extreme value is the maximum or minimum value of a function. If a function has a value everywhere in the neighborhood of a point, and the value of that point is the maximum (minimum), then the value of this function at that point is the maximum (minimum). If it is greater than (less than) the function values of other points in the neighborhood, it is a strict maximum (less than). This point is correspondingly called extreme point or strict extreme point.