A method to obtain the best uniform polynomial approximation for the family of rational function

Fariborzi Araghi, M. A.; Froozanfar, F.

Document Type : Research Paper

Authors

¹ Department of Mathematics, Islamic Azad university, Central Tehran branch

² Ms.student of Mathematics, Islamic Azad university, Kermanshah branch, Kermanshah, Iran

Abstract

In this article, by using Chebyshev’s polynomials and Chebyshev’s expansion, we obtain the best uniform polynomial approximation out of P_2n 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.

Keywords

Main Subjects

References

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Iranian Journal of Optimization

A method to obtain the best uniform polynomial approximation for the family of rational function

References

References

Volume 7, Issue 1 - Serial Number 1
Spring 2015
Pages 753-766

A method to obtain the best uniform polynomial approximation for the family of rational function

References

References

Volume 7, Issue 1 - Serial Number 1Spring 2015Pages 753-766

Volume 7, Issue 1 - Serial Number 1
Spring 2015
Pages 753-766