Formulas for the operator norm and the extension of a linear functional on a linear subspace of a Hilbert Space

Formulas for the operator norm and the extension of a linear functional on a linear subspace of a Hilbert Space

In this paper, formulas  are given  both for  the operator norm and  for the extension of a linear functionaldefined on  a linear subspace of a Hilbert space and the results are illustrated with examples.

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