Geodesic
Best Approximation in Vector Spaces
Matematičeskie zametki, Tome 89 (2011) no. 5, pp. 788-793.

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In this paper, we shall obtain some results on best $f$-approximation in quotient spaces of vector spaces and determine under what conditions $f$-proximinality can be transmitted to and from quotient spaces. Also, in conclusion, we consider the relationship between $f$-approximation subsets and linear functionals on $X$.
Keywords: vector space, $f$-proximinal subspace, $f$-Chebyshev subspace, Hahn–Banach space, linear functional.
Mots-clés : quotient space 
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M. R. Haddadi; H. Mazaheri. Best Approximation in Vector Spaces. Matematičeskie zametki, Tome 89 (2011) no. 5, pp. 788-793. http://geodesic.mathdoc.fr/item/MZM_2011_89_5_a12/

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