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

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.**References**

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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.