Best trigonometric approximation and Dini-Lipschitz classes

  • S. El OuadihEmail author
  • R. Daher


In this paper, we prove an analog of Younis’s result (Younis in Int J Math Math Sci 9(2):301–312, 1986 , Theorem 5.2) on the image under the discrete Fourier–Jacobi transform of a set of functions satisfying the Dini-Lipschitz functions in the space \(\mathbb {L}_{2}^{(\alpha ,\beta )}\).


Fourier–Jacobi series Generalized translation operator Dini-Lipschitz functions 

Mathematics Subject Classification




The authors would like to thank the referee for his valuable comments and suggestions.


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Copyright information

© Springer International Publishing AG 2017

Authors and Affiliations

  1. 1.Department of Mathematics, Faculty of Sciences Aïn ChockUniversity Hassan IICasablancaMorocco

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