Does the series \sum_{n=1}^\infty sin(\frac{1}{n^2}) converge?

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The series ∑_{n=1}^∞ sin(1/n^2) is under consideration for convergence. It can be compared to the series ∑_{n=1}^∞ 1/n^2, which is known to converge. The inequality |sin(x)| ≤ x for x ≥ 0 supports this comparison, as sin(1/n^2) is nonnegative and less than or equal to 1/n^2 for n large enough. The limit comparison test can also be applied, confirming that the original series converges. Therefore, the series ∑_{n=1}^∞ sin(1/n^2) converges.
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Homework Statement


Does the follow serie converge:
\sum_{n=1}^\infty sin(\frac{1}{n^2})

Homework Equations


For serie a_n and b_n if:

A = 0 \leq a_n \leq b_n

if b_n converges then a_n converges

The Attempt at a Solution


I think that I have to use the equation (see 2) and then with

B = \sum_{n=1}^\infty \frac{1}{n^2}

I think that it is larger than A. However I need proof... Any suggestions.

Thanks in advance.
 
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For x>=0, |sin(x)| <= x. (Better yet, on [0,1], 0 <= sin(x) <= x.) Or you can just use the limit comparison test.

Note that both convergence tests require your series to have nonnegative terms.
 
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Question: A clock's minute hand has length 4 and its hour hand has length 3. What is the distance between the tips at the moment when it is increasing most rapidly?(Putnam Exam Question) Answer: Making assumption that both the hands moves at constant angular velocities, the answer is ## \sqrt{7} .## But don't you think this assumption is somewhat doubtful and wrong?

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