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sin(1/(3^n))

Sum of series sin(1/(3^n))



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The solution

You have entered [src]
  oo         
____         
\   `        
 \       /1 \
  \   sin|--|
  /      | n|
 /       \3 /
/___,        
n = 1        
$$\sum_{n=1}^{\infty} \sin{\left(\frac{1}{3^{n}} \right)}$$
Sum(sin(1/(3^n)), (n, 1, oo))
The radius of convergence of the power series
Given number:
$$\sin{\left(\frac{1}{3^{n}} \right)}$$
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
$$a_{n} = \sin{\left(3^{- n} \right)}$$
and
$$x_{0} = 0$$
,
$$d = 0$$
,
$$c = 1$$
then
$$1 = \lim_{n \to \infty} \left|{\frac{\sin{\left(3^{- n} \right)}}{\sin{\left(3^{- (n + 1)} \right)}}}\right|$$
Let's take the limit
we find
False

False
The rate of convergence of the power series
The answer [src]
  oo          
 ___          
 \  `         
  \      / -n\
  /   sin\3  /
 /__,         
n = 1         
$$\sum_{n=1}^{\infty} \sin{\left(3^{- n} \right)}$$
Sum(sin(3^(-n)), (n, 1, oo))
Numerical answer [src]
0.493624088226136227287627379913
0.493624088226136227287627379913
The graph
Sum of series sin(1/(3^n))

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