Glasnik Matematicki, Vol. 44, No.2 (2009), 423-446.

APPROXIMATION BY TRIGONOMETRIC POLYNOMIALS IN WEIGHTED REARRANGEMENT INVARIANT SPACES

Ali Guven and Daniyal M. Israfilov

Department of Mathematics, Faculty of Art and Science, Balikesir University, 10145, Balikesir, Turkey
e-mail: ag_guven@yahoo.com
e-mail: mdaniyal@balikesir.edu.tr

Abstract.   We investigate the approximation properties of trigonometric polynomials and prove some direct and inverse theorems for polynomial approximation in weighted rearrangement invariant spaces.

2000 Mathematics Subject Classification.   41A25, 42A10, 46E30.

Key words and phrases.   Boyd indices, modulus of smoothness, Muckenhoupt class, weighted rearrangement invariant space.

Full text (PDF) (free access)

DOI: 10.3336/gm.44.2.10

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