Degree of Approximation of a Function Belongingto W (Lr, ξ (t)) (r > 1)-Class by (E, 1)(C, 2) Product Summabilty Transform

	International Journal of Mathematical Trends and Technology (IJMTT)
	© 2014 by IJMTT Journal
	Volume-8 Number-2
	Year of Publication : 2014
	Authors : Kusum Sharma , S. S. Malik
	10.14445/22315373/IJMTT-V8P518

Kusum Sharma , S. S. Malik. "Degree of Approximation of a Function Belonging to W (Lr, ξ (t)) (r > 1)-Class by (E, 1)(C, 2) Product Summabilty Transform", International Journal of Mathematical Trends and Technology (IJMTT). V8:136-146 April 2014. ISSN:2231-5373. www.ijmttjournal.org. Published by Seventh Sense Research Group.

Abstract
The field of approximation theory is so vast that it plays an increasingly important role in applications in pure and applied mathematics. The present study deals with a theorem concerning the degree of approximation of a function f belonging to W (Lr, ξ (t)) (r > 1)-class by using (E, 1) (C, 2) of its Fourier series.

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Keywords
Degree of approximation, W (Lr, ξ (t))(r > 1)-class of function, (E, 1) summability, (C, 2) summability, (E, 1) (C, 2) product summability, Fourier series, Lebesgue integral.