Approximation theorems for multivariate Taylor-Abel-Poisson means
Dedicated to Professor Heiner Gonska on the occasion of his 70th anniversary.
DOI:
https://doi.org/10.24193/subbmath.2019.3.03Keywords:
Direct approximation theorem, inverse approximation theorem, Taylor-Abel-Poisson means, K-functional, multiplier.Abstract
We obtain direct and inverse approximation theorems of functions of several variables by Taylor-Abel-Poisson means in the integral metrics. We also show that norms of multipliers in the spaces Lp,Y (Td) are equivalent for all positive integers d.
Mathematics Subject Classification (2010): 41A27, 42A45, 41A35.
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