Comparison Test problem with infinite series

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SUMMARY

The forum discussion focuses on determining the convergence of the series ∑ sin(1/n^2) from 1 to ∞ using the Comparison Test and the Limit Comparison Test. The Limit Comparison Test states that if L = lim[n→∞] An/Bn exists and is greater than 0, then both series converge or diverge together. A user initially struggled with the application of these tests but received guidance to compare sin(1/n^2) with the convergent series 1/n^2, leading to a correct understanding of the Limit Comparison Test.

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  • Understanding of the Comparison Test in series convergence
  • Familiarity with the Limit Comparison Test
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  • Study the proofs and applications of the Comparison Test
  • Learn about the Limit Comparison Test in detail with examples
  • Explore other convergence tests such as the Ratio Test and Root Test
  • Practice solving series convergence problems using various tests
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Students studying calculus, particularly those focusing on series convergence, as well as educators teaching these concepts in mathematics courses.

TheRascalKing
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Homework Statement


I need to use the Comparison Test or the Limit Comparison Test to determine whether or not this series converges:

∑ sin(1/n^2) from 1 to ∞


Homework Equations



Limit Comparison Test: Let {An} and {Bn} be positive sequences. Assume the following limit exists:
L = lim[n→∞] An/Bn
if L>0, then ƩAn converges iff ƩBn converges.
if L = ∞ and ƩAn converges, then ƩBn converges.
if L = 0 and ƩBn converges, then ƩAn converges.

Comparison Test: Assume that there exists M > 0 such that 0 ≤ An ≤ Bn for n ≥ M.
if Ʃ[n=1 to ∞] Bn converges, then Ʃ[n=1 to ∞]An also converges.
if Ʃ[n=1 to ∞] An diverges, then Ʃ[n=1 to ∞]Bn also diverges.

The Attempt at a Solution



I've tried comparing with sin(1/n), sin(n), sin(1/n^3), sin(1/n^4), and a handful of other functions involving sin.

Sorry, I'm new to the comparison test and limit comparison test :/
 
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TheRascalKing said:

Homework Statement


I need to use the Comparison Test or the Limit Comparison Test to determine whether or not this series converges:

∑ sin(1/n^2) from 1 to ∞


Homework Equations



Limit Comparison Test: Let {An} and {Bn} be positive sequences. Assume the following limit exists:
L = lim[n→∞] An/Bn
if L>0, then ƩAn converges iff ƩBn converges.
if L = ∞ and ƩAn converges, then ƩBn converges.
if L = 0 and ƩBn converges, then ƩAn converges.

Comparison Test: Assume that there exists M > 0 such that 0 ≤ An ≤ Bn for n ≥ M.
if Ʃ[n=1 to ∞] Bn converges, then Ʃ[n=1 to ∞]An also converges.
if Ʃ[n=1 to ∞] An diverges, then Ʃ[n=1 to ∞]Bn also diverges.

The Attempt at a Solution



I've tried comparing with sin(1/n), sin(n), sin(1/n^3), sin(1/n^4), and a handful of other functions involving sin.

Sorry, I'm new to the comparison test and limit comparison test :/

Try comparing with 1/n^2. You know that converges, yes?
 
Thanks, got it now. I was using the Limit Comparison test wrong >.<
 

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