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(2*n-3)/(n^2+2)

Sum of series (2*n-3)/(n^2+2)



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The solution

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  oo         
____         
\   `        
 \    2*n - 3
  \   -------
  /     2    
 /     n  + 2
/___,        
n = 1        
$$\sum_{n=1}^{\infty} \frac{2 n - 3}{n^{2} + 2}$$
Sum((2*n - 3)/(n^2 + 2), (n, 1, oo))
The radius of convergence of the power series
Given number:
$$\frac{2 n - 3}{n^{2} + 2}$$
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
$$a_{n} = \frac{2 n - 3}{n^{2} + 2}$$
and
$$x_{0} = 0$$
,
$$d = 0$$
,
$$c = 1$$
then
$$1 = \lim_{n \to \infty}\left(\frac{\left(\left(n + 1\right)^{2} + 2\right) \left|{\frac{2 n - 3}{2 n - 1}}\right|}{n^{2} + 2}\right)$$
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 (2*n-3)/(n^2+2)

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