Measurable Taylor’s theorem: an elementary proof

Author(s): Gianluca Viggiano1
1Bank of Italy, Regional Economic Research, Milan, Italy.
Copyright © Gianluca Viggiano. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

The Taylor expansion is a widely used and powerful tool in all branches of Mathematics, both pure and applied. In Probability and Mathematical Statistics, however, a stronger version of Taylor’s classical theorem is often needed, but only tacitly assumed. In this note, we provide an elementary proof of this measurable Taylor’s theorem, which guarantees that the interpolating point in the Lagrange form of the remainder can be chosen to depend measurably on the independent variable.

Keywords: Trigonometric functions; Sinc function; Inequalities.