Why Does the Sequence {1/n} Converge in R1 but Not in Positive Real Numbers?

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The sequence {1/n} converges to 0 in the metric space R1, as stated on page 48 of "Baby Rudin," but fails to converge in the set of positive real numbers. This is because the limit of the sequence, which is 0, is not included in the set of positive real numbers. The distinction between the two metric spaces is crucial for understanding the convergence behavior of the sequence.

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on page 48 of baby Rudin, it says " the sequence {1/n} converges in R1 to 0, but fails to converge in the set of all positive real numbers [with d(x,y) = |x-y|]."

ok, I know it has something to do with 1/n going to infinity near zero, but it does that whether the metric space is R1 or just the positive reals.

So why is that quote true?
 
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henryN7 said:
on page 48 of baby Rudin, it says " the sequence {1/n} converges in R1 to 0, but fails to converge in the set of all positive real numbers [with d(x,y) = |x-y|]."

ok, I know it has something to do with 1/n going to infinity near zero, but it does that whether the metric space is R1 or just the positive reals.

So why is that quote true?

Because the positive reals do not include zero, the limit of the sequence.
 
awkward said:
Because the positive reals do not include zero, the limit of the sequence.

Ah, thank you.
 

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