Mister Exam

Other calculators


sin(pi/n)^n

Sum of series sin(pi/n)^n



=

The solution

You have entered [src]
  oo          
 ___          
 \  `         
  \      n/pi\
   )  sin |--|
  /       \n /
 /__,         
n = 1         
n=1sinn(πn)\sum_{n=1}^{\infty} \sin^{n}{\left(\frac{\pi}{n} \right)}
Sum(sin(pi/n)^n, (n, 1, oo))
The radius of convergence of the power series
Given number:
sinn(πn)\sin^{n}{\left(\frac{\pi}{n} \right)}
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=sinn(πn)a_{n} = \sin^{n}{\left(\frac{\pi}{n} \right)}
and
x0=0x_{0} = 0
,
d=0d = 0
,
c=1c = 1
then
1=limn(sinn(πn)sinn+1(πn+1))1 = \lim_{n \to \infty}\left(\frac{\left|{\sin^{n}{\left(\frac{\pi}{n} \right)}}\right|}{\left|{\sin^{n + 1}{\left(\frac{\pi}{n + 1} \right)}}\right|}\right)
Let's take the limit
we find
False

False
The rate of convergence of the power series
1.07.01.52.02.53.03.54.04.55.05.56.06.504
Numerical answer [src]
1.98873236754610398181308175190
1.98873236754610398181308175190
The graph
Sum of series sin(pi/n)^n

    Examples of finding the sum of a series