Title of article :
A method to obtain the best uniform polynomial approximation for the family of rational function ax bx c 2 1
Author/Authors :
Fariborzi Araghi, M. A Department of Mathematics - Islamic Azad university - Central Tehran branch , Froozanfar, F Islamic Azad university - Kermanshah branch
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
Journal title :
Astroparticle Physics
