Discontinuity, Nonlinearity, and Complexity
Degree of Approximation of Functions $f(x,y)$ by Double Hausdorff Matrix Summability Method
Discontinuity, Nonlinearity, and Complexity 11(3) (2022) 539551  DOI:10.5890/DNC.2022.09.014
Abhishek Mishra$^1$, Vishnu Narayan Mishra$^2$
$^1$ Department of Mathematics, Netarhat Vidyalaya, Netarhat, Jharkhand, India
$^2$ Department of Mathematics, Indira Gandhi National Tribal University,
Amarkantak, Madhya Pradesh, India
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Abstract
The degree of trigonometric approximation of periodic functions $f(x,y)$ belonging to generalized H\"older class by double Hausdorff matrix summability means of double Fourier series has been obtained in this paper. Some corollaries have also been established to find estimates of approximation using almost Euler means and $\left(C, \gamma, \delta \right)$ means.
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