Why why why (tiny limsup proof)


by quasar987
Tags: limsup, proof, tiny
quasar987
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#1
May11-07, 09:59 PM
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There's a "theorem" in my book that says if x is a cluster point of {x_n}, then lim inf(x_n)[itex]\leq[/itex]x[itex]\leq[/itex]lim sup(x_n).

The way the author proves it is a little bit extravagant. Why not just say "Let A be the set of all cluster points. Then, lim inf(x_n)=inf(A)[itex]\leq[/itex]x[itex]\leq[/itex]sup(A)=lim sup(x_n)."

???
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Dick
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May13-07, 03:10 PM
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Don't they pretty much say the same thing?


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