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n/2^n
  • How to use it?

  • Sum of series:
  • n/2^n n/2^n
  • 1/n 1/n
  • (1)/(2^n+n) (1)/(2^n+n)
  • e^2 e^2
  • Identical expressions

  • n/ two ^n
  • n divide by 2 to the power of n
  • n divide by two to the power of n
  • n/2n
  • n divide by 2^n

Sum of series n/2^n



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The solution

You have entered [src]
  oo    
____    
\   `   
 \    n 
  \   --
  /    n
 /    2 
/___,   
n = 1   
$$\sum_{n=1}^{\infty} \frac{n}{2^{n}}$$
Sum(n/2^n, (n, 1, oo))
The radius of convergence of the power series
Given number:
$$\frac{n}{2^{n}}$$
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
$$a_{n} = n$$
and
$$x_{0} = -2$$
,
$$d = -1$$
,
$$c = 0$$
then
$$\frac{1}{R} = \tilde{\infty} \left(-2 + \lim_{n \to \infty}\left(\frac{n}{n + 1}\right)\right)$$
Let's take the limit
we find
False

$$R = 0$$
The rate of convergence of the power series
The answer [src]
2
$$2$$
2
Numerical answer [src]
2.00000000000000000000000000000
2.00000000000000000000000000000
The graph
Sum of series n/2^n

    Examples of finding the sum of a series