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Research Article | Open | Published:

An Extension of Gregus Fixed Point Theorem


Let be a closed convex subset of a complete metrizable topological vector space and a mapping that satisfies for all , where , , , , , and . Then has a unique fixed point. The above theorem, which is a generalization and an extension of the results of several authors, is proved in this paper. In addition, we use the Mann iteration to approximate the fixed point of .



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Correspondence to JO Olaleru.

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  • Point Theorem
  • Differential Geometry
  • Computational Biology