Hello, i have this exercise where i need to show for a separable Hilbert space there exist some subsequence with a special property. But im stuck even at the beginning, so i hope someone can help me atleast some idea of where to start.
2026-03-27 10:31:45.1774607505
Functional analysis - Hilbert space - Existence of subsequence
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Since every Hilbert space is reflexive it follows from Kakutani's Theorem.