Entisarat El-Shobaky, Sahar Mohammed Ali, Wataru Takahashi, "On projection constant problems and the existence of metric projections in normed spaces", Abstract and Applied Analysis, vol. 6, Article ID 252507, 11 pages, 2001. https://doi.org/10.1155/S1085337501000732
On projection constant problems and the existence of metric projections in normed spaces
We give the sufficient conditions for the existence of a metric projection onto convex closed subsets of normed linear spaces which are reduced conditions than that in the case of reflexive Banach spaces and we find a general formula for the projections onto the maximal proper subspaces of the classical Banach spaces and . We also give the sufficient and necessary conditions for an infinite matrix to represent a projection operator from or onto anyone of their maximal proper subspaces.
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