Weighted variable exponent grand Lebesgue spaces and inequalities of approximation

Abstract

In this paper we discuss and investigate trigonometric approximation in weighted grand variable exponent Lebesgue spaces. We also prove the direct and inverse theorems in these spaces.

Keywords

• weighted grand variable exponent Lebesgue, Sobolev and Lipschitz space
• maximal operator
• modulus of smoothness
• best approximation
• Jackson and inverse theorems
• K-functional

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