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arXiv · 2404.12662

Best Simultaneous Approximation of Functions and a Generalized Minimax Theorem

Shinji Tanimoto
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Abstract

Best simultaneous approximation (BSA) for finitely or infinitely many functions are considered under the uniform norm and other important norms. Characterization theorems for a BSA from a finite-dimensional subspace are obtained by a generalized minimax theorem. From the characterization theorem a strong unicity theorem is also deduced for a BSA.

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Shinji Tanimoto. 2024-04-19. Best Simultaneous Approximation of Functions and a Generalized Minimax Theorem. https://arxiv.org/abs/2404.12662

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