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Universality of methods approximating the derivative

Published online by Cambridge University Press:  17 April 2009

Gerd Herzog
Affiliation:
Mathematisches Institut I, Universität Karlsruhe, D-76128 Karlsruhe, Germany, e-mail: Gerd.Herzog@math.uni-karlsruhe.dee-mail: Roland.Lemmert@math.uni-karlsruhe.de
Roland Lemmert
Affiliation:
Mathematisches Institut I, Universität Karlsruhe, D-76128 Karlsruhe, Germany, e-mail: Gerd.Herzog@math.uni-karlsruhe.dee-mail: Roland.Lemmert@math.uni-karlsruhe.de
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We prove the existence of universal functions for mappings Tn: C([0,1]) → Lp([0,1]), 0 < p < 1, with Tn(f) → f′ (n → ∞) on certain subsets of C1([0,1]). As an application we conclude that there are continuous functions fC([0,1]), such that the derivatives of the Bernstein polynomials form a dense subset of Lp([0,1]) for each 0 < p < 1.

Type
Research Article
Copyright
Copyright © Australian Mathematical Society 2006

References

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