## About this book

### Introduction

In **Fourier Analysis and Approximation of Functions** basics of classical Fourier Analysis are given as well as those of approximation by polynomials, splines and entire functions of exponential type.

In Chapter 1 which has an introductory nature, theorems on convergence, in that or another sense, of integral operators are given. In Chapter 2 basic properties of simple and multiple Fourier series are discussed, while in Chapter 3 those of Fourier integrals are studied.

The first three chapters as well as partially Chapter 4 and classical Wiener, Bochner, Bernstein, Khintchin, and Beurling theorems in Chapter 6 might be interesting and available to all familiar with fundamentals of integration theory and elements of Complex Analysis and Operator Theory. Applied mathematicians interested in harmonic analysis and/or numerical methods based on ideas of Approximation Theory are among them.

In Chapters 6-11 very recent results are sometimes given in certain directions. Many of these results have never appeared as a book or certain consistent part of a book and can be found only in periodics; looking for them in numerous journals might be quite onerous, thus this book may work as a reference source.

The methods used in the book are those of classical analysis, Fourier Analysis in finite-dimensional Euclidean space Diophantine Analysis, and random choice.

### Keywords

Fourier transform Hilbert space Operator theory bigfin calculus harmonic analysis

#### Authors and affiliations

- Roald M. Trigub
- Eduard S. Bellinsky

- 1.Donetsk National UniversityDonetskUkraine
- 2.University of West IndiesBridgetownBarbados

### Bibliographic information