On a theorem of S . S . Bhatia and B .
نویسندگان
چکیده
In this paper some inequalities for Dirichlet’s and Fejer’s kernels proved in [6] are refined and extended. Then we have obtained the conditions for L-convergence of the r-th derivatives of complex trigonometric series. These results are extensions of corresponding Bhatia’s and Ram’s results for complex trigonometric series (case r = 0).
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تاریخ انتشار 2003