Prove that $\displaystyle l2 $ and $\displaystyle H inf$ are separable.
Hints: Consider finitely nonzero sequences of the form (r1,r2,...,rn,0,0,...,0), where each rk is rational.
Thanks
I think this will help: Show that l2 space separable
Will this help (from the part "How is a H separable") :
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