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Some generalizations of Ky Fan’s best approximation theorem

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Analysis in Theory and Applications

Abstract

We pressent new Ky Fan type best approximation theorems for a discontinuous multivalued map on metrizable topological vector spaces and hyperconvex spaces. In addition, fixed point results are derived for the map studied. Our work generalizes severl results in approximation theory.

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Author notes

  1. A. R. Khan

    Present address: Bahauddin Zakaria University, 60800, Multan, Pakistan

Authors and Affiliations

  1. Department of Mathematical Sciences, King Fahd University of Petroleum and Minerals, 31261, Dhahran, Saudi Arabia

    A. R. Khan

  2. Centre for Advanced Studies in Pure and Applied Mathematics, Bahauddin Zakaria University, 60800, Multan, Pakistan

    N. Hussain

  3. Department of Mathematical Sciences, King Fahd University of Petroleum and Minerals, 31261, Dhahran, Saudi Arabia

    A. B. Thaheem

Authors
  1. A. R. Khan
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  2. N. Hussain
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  3. A. B. Thaheem
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Correspondence to A. R. Khan.

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Khan, A.R., Hussain, N. & Thaheem, A.B. Some generalizations of Ky Fan’s best approximation theorem. Anal. Theory Appl. 20, 189–198 (2004). https://doi.org/10.1007/BF02901443

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  • DOI: https://doi.org/10.1007/BF02901443

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