Abstract
A quasicomplementM to a subspaceN of a Banach spaceX is called strict ifM does not contain an infinite-dimensional subspaceM 1 such that the linear manifoldN+M 1 is closed. It is proved that ifX is separable, thenN always admits a strict quasicomplement. We study the properties of the restrictions of the operators of dense imbedding to infinite-dimensional closed subspaces of a space where these operators are defined.
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Additional information
Zaporozhye University, Zaporozhye. Translated from Ukrainskii Matematicheskii Zhurmal, Vol. 46, No. 6, pp. 789–792, June, 1994
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Shevchik, V.V. Strict quasicomplements and the operators of dense imbedding. Ukr Math J 46, 863–867 (1994). https://doi.org/10.1007/BF02658190
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DOI: https://doi.org/10.1007/BF02658190