A method to obtain the best uniform polynomial approximation for the family of rational function
الموضوعات :M. A. Fariborzi Araghi 1 , F. Foroozanfar 2
1 - Department of Mathematics, Islamic Azad university, Central Tehran branch
2 - Ms.student of Mathematics, Islamic Azad university, Kermanshah branch, Kermanshah, Iran
الکلمات المفتاحية: uniform norm, the best uniform polynomial approximation, alternating set, Chebyshev’s polynomials, Chebyshev’s expansion,
ملخص المقالة :
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)-1on 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)-1for both cases b2-4ac L 0and b2-4ac G 0.
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