Does inf(X) Exist and What is Its Value?

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SUMMARY

The infimum of the set X={1/n: n∈N} exists and is equal to 0. The discussion clarifies that the infimum is defined as the greatest lower bound of the set, which in this case is 0, since for every positive ε, there exists an n such that 1/n < ε. Participants emphasized the importance of demonstrating that any number greater than 0 cannot serve as a lower bound for the set.

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Homework Statement


Let X={1/n: n\inN} (where N is the set of natural numbers)
i) Does inf(X) exist?
ii) What is inf(X)?


Homework Equations





The Attempt at a Solution


I think I should try to prove inf(X) exists by considering it a Lower Limit, but I don't know how to go about doing that. Any help would be appreciated!
 
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Just follow the definition.
The infiimum is the greatest number which is least than any other number in X.
 
Well, surely you can guess at what the inf might be, right? Let's say you think that x is the inf. Now, just show that x is a lower bound and if y is bigger than x, then y isn't lower bound.
 

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