Complex approximation of real functions by reciprocals of polynomials

Wulbert, Daniel

doi:10.1090/S0002-9947-1989-0967318-5

Complex approximation of real functions by reciprocals of polynomials
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Trans. Amer. Math. Soc. 316 (1989), 635-652 Request permission

Abstract:

Characterizations are given for local and global best rational approximations to a real function. The characterizations are specialized to reciprocals of polynomials, where they are used to settle some conjectures and questions.

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