Approximation with Positive Linear Operators and Linear Combinations

“This book deals with linear positive operators, one of the central branches of approximation theory, and their combinations, which allows one to increase the degree of approximation. … It is carefully written and organized. In each chapter, remarkable comments and explanatory remarks are expressed that support and extend the basic text. … This significant book can be recommended as a source book to graduate students and researchers in approximation theory.” (Nurhayat İspır, Mathematical Reviews, January, 2018)“The book under review written by two experts in approximation by positive linear operators (PLO, shortly), consists in eight chapters and contains most of the recent results in the topics announced by the contents of the book, very many belonging to the authors. … This book will be of interest to researchers working in approximation theory and for courses in approximation theory for graduate students.” (Sorin Gheorghe Ga, zbMATH 1371.41035, 2017)

• 1. Moments and Linear Combinations of Positive Linear Operators.- 2. Direct Estimates for Approximation by Linear Combinations.- 3. Inverse Estimates and Saturation Results for Linear Combinations.- 4. Voronovskaja Type Estimates.- 5. Pointwise Estimates for Linear Combinations.- 6. Voronovskaja's Theorem in Terms of Weighted Modulus of Continuity.- 7. Direct Estimates for Some New Operators.- 8. Convergence for Operators Based on Pǎltǎanea Basis.- Bibliography.- Index.