Real analysis proof with sequences

koab1mjr
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Homework Statement


Let Sn be a sequence in R

Prove lim Sn= = 0 if and only if lim abs(Sn) = 0

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The Attempt at a Solution



I think this is someone ciruclar logic and that is why I am stuck

Assume lim Sn = 0, thus for n > N implies |Sn| < epsilon or -epsilon < Sn < epsilon. Since Sn and -Sn are less than epsilon |Sn| < Epsilon for sufficently large n.
Now assume lim |Sn|= 0 so ||Sn||< epsilon and using a similar argument show Sn < Epsilon and complete the proof. IS that the way to go?
 
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It's not circular, it's just that proving Sn->0 and |Sn|->0 are pretty much the same thing. Yes, that's the way to go.
 
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