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5/((5n-2)*(5n+3))
Sum of series/ 5/((5n-2)*(5n+3))

Sum of series 5/((5n-2)*(5n+3))


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The solution

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  oo                     
 ___                     
 \  `                    
  \            5         
   )  -------------------
  /   (5*n - 2)*(5*n + 3)
 /__,                    
n = 1
$$\sum_{n=1}^{\infty} \frac{5}{\left(5 n - 2\right) \left(5 n + 3\right)}$$ 
Sum(5/(((5*n - 2)*(5*n + 3))), (n, 1, oo))
The radius of convergence of the power series
Given number:
$$\frac{5}{\left(5 n - 2\right) \left(5 n + 3\right)}$$
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
$$a_{n} = \frac{5}{\left(5 n - 2\right) \left(5 n + 3\right)}$$
and
$$x_{0} = 0$$
,
$$d = 0$$
,
$$c = 1$$
then
$$1 = \lim_{n \to \infty}\left(\left(5 n + 8\right) \left|{\frac{1}{5 n - 2}}\right|\right)$$
Let's take the limit
we find
True

False
The rate of convergence of the power series
The answer [src] 
5*Gamma(13/5)
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24*Gamma(8/5)
$$\frac{5 \Gamma\left(\frac{13}{5}\right)}{24 \Gamma\left(\frac{8}{5}\right)}$$ 
5*gamma(13/5)/(24*gamma(8/5))
Numerical answer [src] 
0.333333333333333333333333333333
0.333333333333333333333333333333
The graph
Sum of series 5/((5n-2)*(5n+3))

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