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

Sum of series 1/(n^2-3n+2)



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The solution

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  oo              
____              
\   `             
 \         1      
  \   ------------
  /    2          
 /    n  - 3*n + 2
/___,             
n = 1             
n=11(n23n)+2\sum_{n=1}^{\infty} \frac{1}{\left(n^{2} - 3 n\right) + 2}
Sum(1/(n^2 - 3*n + 2), (n, 1, oo))
The radius of convergence of the power series
Given number:
1(n23n)+2\frac{1}{\left(n^{2} - 3 n\right) + 2}
It is a series of species
an(cxx0)dna_{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:
Rd=x0+limnanan+1cR^{d} = \frac{x_{0} + \lim_{n \to \infty} \left|{\frac{a_{n}}{a_{n + 1}}}\right|}{c}
In this case
an=1n23n+2a_{n} = \frac{1}{n^{2} - 3 n + 2}
and
x0=0x_{0} = 0
,
d=0d = 0
,
c=1c = 1
then
1=limn3n(n+1)2+1n23n+21 = \lim_{n \to \infty} \left|{\frac{3 n - \left(n + 1\right)^{2} + 1}{n^{2} - 3 n + 2}}\right|
Let's take the limit
we find
True

False
The rate of convergence of the power series
2.07.02.53.03.54.04.55.05.56.06.50.02-0.02
The answer [src]
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nan
The graph
Sum of series 1/(n^2-3n+2)

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