Abstract

The Takagi function is a classical example of a continuous nowhere differentiable function. In this paper we prove that it is nowhere approximately derivable.

Author information

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Juan Ferrera

Dep. de Análisis Matemático, Facultad Ciencias Matemáticas, Universidad Complutense, 28040 Madrid, Spain

ferrera@mat.ucm.es

Javier Gómez-Gil

Dep. de Análisis Matemático, Facultad Ciencias Matemáticas, Universidad Complutense, 28040 Madrid, Spain

gomezgil@mat.ucm.es

Keywords

  • Approximate differentiability
  • Takagi function

Mathematics Subject Classification

26A27, 26A24

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Suggested citation

J. Ferrera, J. Gómez-Gil. “Non Approximate Derivability of the Takagi Function.” Journal of Convex Analysis 27 (2020), No. 1, 307–312. https://doi.org/10.68381/jca27017

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Published by Heldermann Verlag, 2020. Rights now held by Banach Press LLC.