A simple proof of the closed graph theorem
DOI:
https://doi.org/10.14419/gjma.v4i1.5534Keywords:
Closed Graph Theorem, Closed Linear Operator, Uniform Boundedness Principle, New Short Proof of The Closed Graph TheoremAbstract
Assume that A is a closed linear operator defined on all of a Hilbert space H. Then, A is bounded. This classical theorem is proved on the basis of uniform boundedness principle. The proof is easily extended to Banach spaces.
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