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Trigonometric approximation in $L_{p}$-norm. (English) Zbl 1057.42004
Summary: We weaken the conditions of monotonicity given by {\it P. Chandra} [J. Math. Anal. Appl. 275, No. 1, 13--26 (2002; Zbl 1011.42001)], where he investigated trigonometric polynomials associated with $f \in \text{Lip}(\alpha,p)$ $(0<\alpha \leqslant 1, p \geqslant 1)$ to approximate $f$ in $L_p$-norm to the degree of $O(n^{-\alpha}) (0<\alpha \leqslant 1)$.

##### MSC:
 42A10 Trigonometric approximation
Full Text:
##### References:
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