Sharp estimates for deviations of the Faward sums on classes of continuous periodic functions of two variables

1981 ◽  
Vol 32 (4) ◽  
pp. 367-374
Author(s):  
A. I. Stepanets
Keyword(s):  
Periodic Functions ◽  
Sharp Estimates ◽  
Functions Of Two Variables

scholarly journals Some sharp inequalities for approximations of periodic functions in $L_1$ space

1987 ◽  
pp. 4
Author(s):  
V.F. Babenko
Keyword(s):  
Periodic Functions ◽  
Piecewise Constant ◽  
Sharp Estimates ◽  
Alpha Beta

We provide sharp estimates of Jackson's inequalities type for the best $(\alpha, \beta)$-approximations in the space $L_1$ of periodic functions that are representable as the convolution of the kernel $K$ that does not increase the number of sign alternations with functions $\varphi \in C$, by means of convolutions of the kernel $K$ with the functions that are piecewise-constant in the intervals $\bigl( \frac{l \pi}{n}, \frac{(l+1)\pi}{n} \bigr)$.

scholarly journals On approximation, in the strong sense, of functions of two variables by trigonometric polynomials

2021 ◽  
pp. 20
Author(s):  
V.V. Lipovik ◽  
N.P. Khoroshko
Keyword(s):  
Strong Sense ◽  
Trigonometric Polynomials ◽  
Asymptotic Estimates ◽  
Periodic Functions ◽  
Functions Of Two Variables

In the paper, we have found order asymptotic estimates of approximations, in the strong sense, relative to given matrix of classes of continuous periodic functions of two variables by some trigonometric polynomials.

Sign in / Sign up

Export Citation Format

Share Document