Theory of Approximation of Functions of a Real Variable discusses a number of fundamental parts of the modern theory of approximation of functions of a real var

This is an easily accessible account of the approximation of functions. It is simple and without unnecessary details, but complete enough to include the classic

Mathematics of Computing -- Numerical Analysis.

This is a textbook on classical polynomial and rational approximation theory for the twenty-first century. Aimed at advanced undergraduates and graduate student

This undergraduate textbook is based on lectures given by the author on the differential and integral calculus of functions of several real variables. The book