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ln^2n/n

Sum of series ln^2n/n



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The solution

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  oo         
____         
\   `        
 \       2   
  \   log (n)
  /   -------
 /       n   
/___,        
n = 1        
$$\sum_{n=1}^{\infty} \frac{\log{\left(n \right)}^{2}}{n}$$
Sum(log(n)^2/n, (n, 1, oo))
The radius of convergence of the power series
Given number:
$$\frac{\log{\left(n \right)}^{2}}{n}$$
It is a series of species
$$a_{n} \left(c x - x_{0}\right)^{d n}$$
- power series.
The radius of convergence of a power series can be calculated by the formula:
$$R^{d} = \frac{x_{0} + \lim_{n \to \infty} \left|{\frac{a_{n}}{a_{n + 1}}}\right|}{c}$$
In this case
$$a_{n} = \frac{\log{\left(n \right)}^{2}}{n}$$
and
$$x_{0} = 0$$
,
$$d = 0$$
,
$$c = 1$$
then
$$1 = \lim_{n \to \infty}\left(\frac{\left(n + 1\right) \log{\left(n \right)}^{2}}{n \log{\left(n + 1 \right)}^{2}}\right)$$
Let's take the limit
we find
True

False
The rate of convergence of the power series
Numerical answer
The series diverges
The graph
Sum of series ln^2n/n

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