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1^(n-1)/8^n
  • How to use it?

  • Sum of series:
  • 3i
  • n^2*x^n
  • (n^3+n+5)/(n+6) (n^3+n+5)/(n+6)
  • x^(n-1)/(n!)^(1/2)
  • Identical expressions

  • one ^(n- one)/ eight ^n
  • 1 to the power of (n minus 1) divide by 8 to the power of n
  • one to the power of (n minus one) divide by eight to the power of n
  • 1(n-1)/8n
  • 1n-1/8n
  • 1^n-1/8^n
  • 1^(n-1) divide by 8^n
  • Similar expressions

  • 1^(n+1)/8^n

Sum of series 1^(n-1)/8^n



=

The solution

You have entered [src]
  oo        
____        
\   `       
 \     n - 1
  \   1     
   )  ------
  /      n  
 /      8   
/___,       
n = 1       
$$\sum_{n=1}^{\infty} \frac{1^{n - 1}}{8^{n}}$$
Sum(1^(n - 1)/8^n, (n, 1, oo))
The radius of convergence of the power series
Given number:
$$\frac{1^{n - 1}}{8^{n}}$$
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
$$a_{n} = 1$$
and
$$x_{0} = -8$$
,
$$d = -1$$
,
$$c = 0$$
then
$$\frac{1}{R} = \tilde{\infty} \left(-8 + \lim_{n \to \infty} 1\right)$$
Let's take the limit
we find
False

$$R = 0$$
The rate of convergence of the power series
The answer [src]
1/7
$$\frac{1}{7}$$
1/7
Numerical answer [src]
0.142857142857142857142857142857
0.142857142857142857142857142857
The graph
Sum of series 1^(n-1)/8^n

    Examples of finding the sum of a series