What are the differences between derived and closure points in sets?

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SUMMARY

The discussion focuses on the differences between derived points and closure points in set theory, specifically using the example of the set {1/n : n in Naturals}. The derived point of this set is {0}, while the closure points include all elements of the set along with {0}, resulting in the closure being S ∪ {0}. The conversation also touches on the concept of a "base," which is related to generators in topology, indicating a need for clarity in definitions.

PREREQUISITES
  • Understanding of set theory terminology, including derived points and closure points.
  • Familiarity with the concept of limits in mathematical analysis.
  • Basic knowledge of topology, particularly the definition of a base.
  • Ability to work with sequences and their convergence properties.
NEXT STEPS
  • Study the definitions and properties of derived points and closure points in set theory.
  • Explore the concept of a base in topology and its relation to generators.
  • Investigate examples of sets with distinct derived and closure points.
  • Learn about convergence and limits in sequences to better understand derived points.
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Mathematics students, educators, and anyone seeking to deepen their understanding of set theory and topology, particularly in the context of derived and closure points.

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Homework Statement


I am looking for examples of sets that have derived pts that are different from closure pts because I am trying to understand them better.

Also, if you can , please try to bring the word "base" into this. I do not understand quite fully a base. I know the definition and I know it is similar to a generator. (I hope)


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The Attempt at a Solution



I know that {1/n : n in Naturals} has D-pt {0} and closure pts {all set}
 
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I'm not sure you are using very standard terminology. Can you state the definitions of your words? I would say the closure of S={1/n} is S union {0}.
 
Your right, I'm sorry. My closure was wrong
 

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