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Differential Equations

, Volume 55, Issue 1, pp 8–23 | Cite as

Convergence of the Spectral Expansion in the Eigenfunctions of a Fourth-Order Differential Operator

  • V. M. KurbanovEmail author
  • Kh. R. Godzhaeva
Ordinary Differential Equations
  • 7 Downloads

Abstract

We study the convergence of spectral expansions of functions of the class W p 1 (G), p ≥ 1, G = (0, 1), in the eigenfunctions of an ordinary differential operator of even order with integrable coefficients. Sufficient conditions for absolute and uniform convergence are obtained and the rate of uniform convergence of these expansions on the interval ̅G is found.

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© Pleiades Publishing, Ltd. 2019

Authors and Affiliations

  1. 1.Institute of Mathematics and MechanicsNational Academy of Sciences of AzerbaijanBakuAzerbaijan
  2. 2.N. Tusi Azerbaijan State Pedagogical UniversityBakuAzerbaijan

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