Abstract
We obtain estimates exact in order for the best trigonometric and orthogonal trigonometric approximations of the classesL β,ρΨ of functions of one variable in the spaceL q in the case 2<p <q < ∞.
References
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Translated from Ukrainskii Matematicheskii Zhurnal, Vol. 51, No. 12, pp. 1719–1721, December, 1999.
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Fedorenko, A.S. On the bestm-term trigonometric and orthogonal trigonometric approximations of functions from the classesL β,ρΨ . Ukr Math J 51, 1945–1949 (1999). https://doi.org/10.1007/BF02525137
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DOI: https://doi.org/10.1007/BF02525137