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Convergence a.e. and of norms implies that in Lebesgue space
Let $\lbrace f_n \rbrace$ be a sequence of functions in $L^p$ ($1 \leq p < \infty)$ that converge almost everywhere to a function $f$ in $L^p$.
What's the shortest proof showing that $f_n \rightarrow f$ in $L^p$ if and only if $||f_n ||\rightarrow ||f||$?
I'm trying to shorten proofs as I'm reviewing for exams, and looking for shorter proofs has helped me remember stuff.
– user58191 Jan 19 '13 at 19:03