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A note on uniform approximation of functions having a double pole
Part of:Numerical approximation and computational geometryAlgorithms - Computer ScienceOther special functionsComputational aspects and applicationsApproximations and expansions
Published online by Cambridge University Press: 01 May 2014
Abstract
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We consider the classical problem of finding the best uniform approximation by polynomials of 
$1/(x-a)^2,$ where 
$a>1$ is given, on the interval 
$[-\! 1,1]$ . First, using symbolic computation tools we derive the explicit expressions of the polynomials of best approximation of low degrees and then give a parametric solution of the problem in terms of elliptic functions. Symbolic computation is invoked then once more to derive a recurrence relation for the coefficients of the polynomials of best uniform approximation based on a Pell-type equation satisfied by the solutions.
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- Research Article
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- © The Author(s) 2014
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