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x/(x-1)

Sum of series x/(x-1)



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The solution

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

False
The rate of convergence of the power series
The answer [src]
oo
$$\infty$$
oo
Numerical answer
The series diverges
The graph
Sum of series x/(x-1)

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