Mister Exam

Other calculators

Sum of series arcsin(n+1/n^2)



=

The solution

You have entered [src]
  oo              
____              
\   `             
 \        /    1 \
  \   asin|n + --|
  /       |     2|
 /        \    n /
/___,             
n = 1             
n=1asin(n+1n2)\sum_{n=1}^{\infty} \operatorname{asin}{\left(n + \frac{1}{n^{2}} \right)}
Sum(asin(n + 1/(n^2)), (n, 1, oo))
The radius of convergence of the power series
Given number:
asin(n+1n2)\operatorname{asin}{\left(n + \frac{1}{n^{2}} \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=asin(n+1n2)a_{n} = \operatorname{asin}{\left(n + \frac{1}{n^{2}} \right)}
and
x0=0x_{0} = 0
,
d=0d = 0
,
c=1c = 1
then
1=limnasin(n+1n2)asin(n+1+1(n+1)2)1 = \lim_{n \to \infty} \left|{\frac{\operatorname{asin}{\left(n + \frac{1}{n^{2}} \right)}}{\operatorname{asin}{\left(n + 1 + \frac{1}{\left(n + 1\right)^{2}} \right)}}}\right|
Let's take the limit
we find
1=limnasin(n+1n2)asin(n+1+1(n+1)2)1 = \lim_{n \to \infty} \left|{\frac{\operatorname{asin}{\left(n + \frac{1}{n^{2}} \right)}}{\operatorname{asin}{\left(n + 1 + \frac{1}{\left(n + 1\right)^{2}} \right)}}}\right|
False
The answer [src]
  oo              
____              
\   `             
 \        /    1 \
  \   asin|n + --|
  /       |     2|
 /        \    n /
/___,             
n = 1             
n=1asin(n+1n2)\sum_{n=1}^{\infty} \operatorname{asin}{\left(n + \frac{1}{n^{2}} \right)}
Sum(asin(n + n^(-2)), (n, 1, oo))

    Examples of finding the sum of a series