Approximation by trigonometric polynomials in morrey spaces
Transactions Issue Mathematics, Azerbaijan National Academy of Sciences, cilt.39, sa.1, ss.24-37, 2019 (Scopus)
- Yayın Türü: Makale / Tam Makale
- Cilt numarası: 39 Sayı: 1
- Basım Tarihi: 2019
- Dergi Adı: Transactions Issue Mathematics, Azerbaijan National Academy of Sciences
- Derginin Tarandığı İndeksler: Scopus
- Sayfa Sayıları: ss.24-37
- Anahtar Kelimeler: Best approximation, Modulus of smoothness, Morrey space
- Ankara Üniversitesi Adresli: Evet
Özet
© 2019, Institute of Mathematics and Mechanics, National Academy of Sciences of Azerbaijan. All rights reserved.In this paper, we investigate the best approximation by trigonometric polynomials in Morrey space Lp,λ (I0) with 1 < p < ∞ and I0 = [0, 2π]. We prove the direct and inverse theorems of approximation by trigonometric polynomials in the spacesLp,λ (I0) the closure of C∞ (I0) in Lp,λ (I0). To prove these theorems we get the characterization of K−functionals in terms of the modulus of smoothness and give the Bernstein type inequality for trigonometric polynomials in the spaces Lp,λ (I0).