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TaPaKaH
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Homework Statement
Let [itex](X,\|\cdot\|)[/itex] be a reflexive Banach space. Let [itex]\{T_n\}_{n\in\mathbb{N}}[/itex] be a sequence of bounded linear operators from [itex]X[/itex] into [itex]X[/itex] such that [itex]\lim_{n\to\infty}f(T_nx)[/itex] exists for all [itex]f\in X'[/itex] and [itex]x\in X[/itex].
Use the Uniform Boundedness Principle (twice) to show that [itex]\sup_{n\in\mathbb{N}}\|T_n'\|<\infty[/itex].
Homework Equations
For operators between normed spaces we have [itex]\|T'\|=\|T\|[/itex], but I'm not sure if this can help in this case.
The Attempt at a Solution
I am currently at loss how to deal with information on functions [itex]f[/itex] to apply UBP.
Any hints welcome.