Skip to main content
Log in

Liouville–Weyl derivatives, best approximations, and moduli of smoothness

  • Published:
Acta Mathematica Hungarica Aims and scope Submit manuscript

Abstract

We obtain estimates of norms, best approximations, and moduli of smoothness of the generalized Liouville–Weyl derivatives. The concept of general monotone sequences plays the key role in our study.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Similar content being viewed by others

References

  1. Bernstein S.: On the best approximation of continuous functions by polynomials of a given degree. Comm. Soc. Math. Kharkow, Ser. 2(13), 49–194 (1912)

    Google Scholar 

  2. Butzer P. L., Dyckhoff H., Görlich E., Stens R. L.: Best trigonometric approximation, fractional order derivatives and Lipschitz classes. Canad. J. Math., 29, 781–793 (1977)

    Article  MATH  MathSciNet  Google Scholar 

  3. R. DeVore and G. G. Lorentz, Constructive Approximation, Springer-Verlag (Berlin, 1993).

  4. Ditzian Z., Tikhonov S.: Moduli of smoothnes of functions and their derivatives. Studia Math., 180, 143–160 (2007)

    Article  MATH  MathSciNet  Google Scholar 

  5. Ditzian Z., Hristov V. H., Ivanov K. G.: Moduli of smoothness and K-functionals in L p , 0 < p < 1. Constr. Approximation, 11, 67–83 (1995)

    Article  MATH  MathSciNet  Google Scholar 

  6. H. Johnen and K. Scherer, On the equivalence of the K-functional and moduli of continuity and some applications, in: Constructive Theory of Functions of Several Variables (Proc. Conf., Math. Res. Inst., Oberwolfach (1976)), Lecture Notes in Math., 571, Springer-Verlag (Berlin-Heidelberg, 1977), pp. 119–140.

  7. Liflyand E., Tikhonov S.: A concept of general monotonicity and application. Math. Nachr., 284, 1083–1098 (2011)

    Article  MATH  MathSciNet  Google Scholar 

  8. B. V. Simonov, Properties of a transformed Fourier series, Manuscript no. 3031-81 deposited at VINITI (1981).

  9. Simonov B., Tikhonov S.: On embeddings of functional classes defined by constructive characteristics. Banach Center Publications, 72, 285–307 (2006)

    Article  MathSciNet  Google Scholar 

  10. Simonov B., Tikhonov S.: Embedding theorems in constructive approximation. Sbornik, 199, 1367–1407 (2008)

    Article  MATH  MathSciNet  Google Scholar 

  11. Steckin S. B.: On best approximation of conjugate functions by trigonometric polynomials. Izv. Akad. Nauk SSSR, 20, 197–206 (1956)

    MathSciNet  Google Scholar 

  12. Taberski R.: Differences, moduli and derivatives of fractional orders. Comment. Math. Prace Mat., 19, 389–400 (1977)

    MATH  MathSciNet  Google Scholar 

  13. Tikhonov S.: Trigonometric series with general monotone coefficients. J. Math. Anal. Appl., 326, 721–735 (2007)

    Article  MATH  MathSciNet  Google Scholar 

  14. Tikhonov S., Trebels W.: Ulyanov-type inequalities and generalized Liouville derivatives. Proc. Roy. Soc. Edinburgh Sect. A, 141, 205–224 (2011)

    Article  MATH  MathSciNet  Google Scholar 

  15. A. Zygmund, Trigonometric Series, Vol. I. II, Third edition (Cambridge, 2002).

Download references

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to A. Jumabayeva.

Additional information

This research was partially supported by the MTM 2011-27637, 2014 SGR 289.

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Jumabayeva, A. Liouville–Weyl derivatives, best approximations, and moduli of smoothness. Acta Math. Hungar. 145, 369–391 (2015). https://doi.org/10.1007/s10474-015-0485-x

Download citation

  • Received:

  • Revised:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s10474-015-0485-x

Key words and phrases

Mathematics Subject Classification

Navigation