Fariborzi Araghi, M., Froozanfar, F. (2015). A method to obtain the best uniform polynomial approximation for the family of rational function. Iranian Journal of Optimization, 7(1), 753-766.
M. A. Fariborzi Araghi; F. Froozanfar. "A method to obtain the best uniform polynomial approximation for the family of rational function". Iranian Journal of Optimization, 7, 1, 2015, 753-766.
Fariborzi Araghi, M., Froozanfar, F. (2015). 'A method to obtain the best uniform polynomial approximation for the family of rational function', Iranian Journal of Optimization, 7(1), pp. 753-766.
Fariborzi Araghi, M., Froozanfar, F. A method to obtain the best uniform polynomial approximation for the family of rational function. Iranian Journal of Optimization, 2015; 7(1): 753-766.
A method to obtain the best uniform polynomial approximation for the family of rational function
1Department of Mathematics, Islamic Azad university, Central Tehran branch
2Ms.student of Mathematics, Islamic Azad university, Kermanshah branch, Kermanshah, Iran
Receive Date: 20 September 2014,
Revise Date: 20 November 2014,
Accept Date: 20 November 2014
Abstract
In this article, by using Chebyshev’s polynomials and Chebyshev’s expansion, we obtain the best uniform polynomial approximation out of P2n to a class of rational functions of the form (ax2+c)-1 on any non symmetric interval [d,e]. Using the obtained approximation, we provide the best uniform polynomial approximation to a class of rational functions of the form (ax2+bx+c)-1 for both cases b2-4ac L 0 and b2-4ac G 0.
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