Open AccessPointwise approximation of modified conjugate functions by matrix operators of their Fourier series with the use of some parameters
Author(s) -
Bogdan Szal,
Włodzimierz Łenski
Publication year - 2020
Publication title -
tamkang journal of mathematics
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.324
H-Index - 18
eISSN - 0049-2930
pISSN - 2073-9826
DOI - 10.5556/j.tkjm.51.2020.3080
Subject(s) - pointwise , mathematics , conjugate , fourier series , series (stratigraphy) , measure (data warehouse) , matrix (chemical analysis) , pure mathematics , function (biology) , pointwise convergence , combinatorics , mathematical analysis , discrete mathematics , computer science , paleontology , approx , materials science , database , evolutionary biology , composite material , biology , operating system
We extend and generalize the results of Xh. Z. Krasniqi [Acta Comment. Univ.Tartu. Math. 17 (2013), 89-101] and the authors [Acta Comment. Univ. Tartu.Math. 13 (2009), 11-24], [Proc. Estonian Acad. Sci. 2018, 67, 1, 50--60] aswell the jont paper with M. Kubiak [Journal of Inequalities and Applications(2018) 2018:92]. We consider the modified conjugate function $\widetilde{f}%_{r}$ for $2\pi /\rho $--periodic function $f$ . Moreover, the measure ofapproximations depends on \textbf{\ }$\mathbf{\rho }$\textbf{ - }differencesof the entries of matrices defined the method of summability.