Best polynomial approximations in L2 of classes of 2π-periodic functions and exact values of their widths

被引：0
作者：
M. Sh. Shabozov
G. A. Yusupov
机构：
[1] Academy of Sciences of Tajikistan,Institute of Mathematics
[2] Tajik National University,undefined
来源：
Mathematical Notes | 2011年 / 90卷
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摘要：
We find sharp inequalities between the best approximations of periodic differentiable functions by trigonometric polynomials and moduli of continuity ofmth order in the space L2 as well as present their applications. For some classes of functions defined by these moduli of continuity, we calculate the exact values of n-widths in L2.
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页码：748 / 757
页数：9
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