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 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.
Keywords
- Chebyshev’s polynomials
- Chebyshev’s expansion
- uniform norm
- the best uniform polynomial approximation
- alternating set
Main Subjects
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