Mean value theorem

In mathematics, the mean value theorem states, roughly, that for a given planar arc between two endpoints, there is at least one point at which the tangent to the arc is parallel to the secant through its endpoints. It is one of the most important results in real analysis. This theorem is used to prove statements about a function on an interval starting from local hypotheses about derivatives at points of the interval.

For any function that is continuous on and differentiable on there exists some in the interval such that the secant joining the endpoints of the interval is parallel to the tangent at .

More precisely, the theorem states that if is a continuous function on the closed interval and differentiable on the open interval , then there exists a point in such that the tangent at is parallel to the secant line through the endpoints and , that is,


Share this article:

This article uses material from the Wikipedia article Mean value theorem, and is written by contributors. Text is available under a CC BY-SA 4.0 International License; additional terms may apply. Images, videos and audio are available under their respective licenses.