Детальный поиск

Отменить
Найденный: 3 Экземпляр 0.000 sn
- Вы можете использовать опцию И / ИЛИ / НЕ для критериев, которые вы хотите добавить или.
- Вы можете вернуться к обычному поиску, нажав кнопку Отмена.
Фильтры
Доступ к файлам

Bernstein-Nikolskii-Markov-type inequalities for algebraic polynomials in a weighted Lebesgue space

Meerim İmaş Kızı | Fahreddin ABDULLAYEV

In this paper, we study Bernstein, Markov and Nikol’skii type inequalities for arbitrary algebraic polynomials with respect to a weighted Lebesgue space, where the contour and weight functions have some singularities on a given contour. Keyword: In this paper, we study Bernstein, Markov and Nikol’skii type inequalities for arbitrary algebraic polynomials with respect to a weighted Lebesgue space, where the contour and weight functions have some singularities on a given contour

Доступ к файлам

Fejér-type positive operator based on Takenaka-Malmquist system on unit circle

Fahreddin ABDULLAYEV

Let φ={φk}k=−∞∞ denote the extended Takenaka–Malmquist system on unit circle T and let σn,φ(f), f∈L1(T), be the Fejér-type operator based on φ, introduced by V. N. Rusak. We give the convergence criteria for σn,φ(f) in Banach space C(T). Also we prove the Voronovskaya-type theorem for σn,φ(f) on class of holomorphic functions representable by Cauchy-type integrals with bounded densities. Keywords: Holomorphic functions; Takenaka–Malmquist system; Fejér type operator; Blaschke product; Frostman condition

Доступ к файлам

Best approximation-preserving operators over Hardy space

Fahreddin ABDULLAYEV

Let Tn be the linear Hadamard convolution operator acting over Hardy space Hq, 1≤q≤∞. We call Tn a best approximation-preserving operator (BAP operator) if Tn(en)=en, where en(z):=zn, and if ∥Tn(f)∥q≤En(f)q for all f∈Hq, where En(f)q is the best approximation by algebraic polynomials of degree a most n−1 in Hq space. We give necessary and sufficient conditions for Tn to be a BAP operator over H∞. We apply this result to establish an exact lower bound for the best approximation of bounded holomorphic functions. In particular, we show that the Landau-type inequality ∣∣fˆn∣∣+c∣∣fˆN∣∣≤En(f)∞, wher ...Более

Наши обязательства и политика в отношении файлов cookie подпадает под действие закона ТР защите персональных данных № 6698.
Да

creativecommons
Bu site altında yer alan tüm kaynaklar Creative Commons Alıntı-GayriTicari-Türetilemez 4.0 Uluslararası Lisansı ile lisanslanmıştır.
Platforms