Sequence Limit (abstract math)

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SUMMARY

The discussion focuses on proving that if sequences \(x_n\) and \(y_n\) converge to limits \(L\) and \(M\) respectively, then the difference \(x_n - y_n\) converges to \(L - M\). The proof utilizes the definition of limits, specifically the triangle inequality, to establish that \(|(x_n - y_n) - (L - M)|\) can be bounded by the sum of the individual limits' deviations. The conclusion is that the approach is valid, and any discrepancies in results likely stem from minor calculation errors.

PREREQUISITES
  • Understanding of sequences and their limits
  • Familiarity with the definition of limit in mathematical analysis
  • Knowledge of the triangle inequality in real analysis
  • Basic algebraic manipulation of inequalities
NEXT STEPS
  • Study the formal definition of limits in sequences
  • Learn about the triangle inequality and its applications in proofs
  • Explore convergence criteria for sequences in real analysis
  • Practice proving limit properties with various sequences
USEFUL FOR

Students of mathematics, particularly those studying real analysis, educators teaching limit concepts, and anyone interested in the foundational principles of convergence in sequences.

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Homework Statement



If x_n[tex]\rightarrow[/tex] L and y_n [tex]\rightarrow[/tex] M

prove that

x_n - y_n [tex]\rightarrow[/tex] L-M

Homework Equations



Definition of Limit

The Attempt at a Solution



I followed and stayed within the definition of limit of a sequence, but I got 0 for x_n - y_n.
 
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Can you show us what you did then? Probably your approach is correct but you made a small mistake somewhere.
 
[itex]|(x_n- y_n)- (L- M)|= |(x_n- L)+ (-y_n+ M)|\le |x_n-L|+ |-y_n+ M|[/itex]
 

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