Series Convergence: Show AK -> 0 as K->∞

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SUMMARY

The discussion focuses on proving that if the series \(\sum a_k\) converges, then the limit of the sequence \(a_k\) approaches zero as \(k\) approaches infinity. Participants emphasize the importance of understanding the definition of convergence through partial sums. The proof involves establishing that for any real number \(c\) and \(\epsilon > 0\), there exists an integer \(N\) such that for all \(n > N\), the absolute difference \(|a_n - c| < \epsilon\). This indicates that the terms of the series must approach zero as \(k\) increases.

PREREQUISITES
  • Understanding of series convergence and divergence
  • Familiarity with the epsilon-delta definition of limits
  • Knowledge of partial sums in the context of infinite series
  • Basic concepts of real analysis
NEXT STEPS
  • Study the definition of convergence for series in real analysis
  • Learn about the properties of convergent sequences
  • Explore the relationship between series and their partial sums
  • Investigate examples of convergent and divergent series
USEFUL FOR

Students of mathematics, particularly those studying real analysis, educators teaching series convergence, and anyone seeking to deepen their understanding of infinite series and their properties.

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Homework Statement



Show that if \sumak converges, then \sum from k to ∞ of ak goes to zero as k goes to ∞.

Homework Equations



The Attempt at a Solution



I'm not really sure how to go about this proof. But, this is my attempt,

First I tried to show that \sumak is convergent.

Let c be a real number and ε > 0. So there is an integer N > 0 such that if n > N then |an - c | < ε.

So c is the limit of the sequence and an -> c.

I don't really know where to go from there. Any help is appreciated.
 
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The definition of convergence of a series uses partial sums. What's the sum from k to infinity in terms of a partial sum?
 

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