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(-1)/(2n-1)!
Sum of series/ (-1)/(2n-1)!

Sum of series (-1)/(2n-1)!


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The solution

You have entered [src] 
  oo            
 ___            
 \  `           
  \      -1     
   )  ----------
  /   (2*n - 1)!
 /__,           
n = 1
∑n=1∞−1(2n−1)!\sum_{n=1}^{\infty} - \frac{1}{\left(2 n - 1\right)!} 
Sum(-1/factorial(2*n - 1), (n, 1, oo))
The radius of convergence of the power series
Given number:
−1(2n−1)!- \frac{1}{\left(2 n - 1\right)!}
It is a series of species
an(cx−x0)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+lim⁡n→∞∣anan+1∣cR^{d} = \frac{x_{0} + \lim_{n \to \infty} \left|{\frac{a_{n}}{a_{n + 1}}}\right|}{c}
In this case
an=−1(2n−1)!a_{n} = - \frac{1}{\left(2 n - 1\right)!}
and
x0=0x_{0} = 0
,
d=0d = 0
,
c=1c = 1
then
1=lim⁡n→∞∣(2n+1)!(2n−1)!∣1 = \lim_{n \to \infty} \left|{\frac{\left(2 n + 1\right)!}{\left(2 n - 1\right)!}}\right|
Let's take the limit
we find
False

False
The rate of convergence of the power series
1.07.01.52.02.53.03.54.04.55.05.56.06.5-1.2-0.8
The answer [src] 
-sinh(1)
−sinh⁡(1)- \sinh{\left(1 \right)} 
-sinh(1)
Numerical answer [src] 
-1.17520119364380145688238185060
-1.17520119364380145688238185060
The graph
Sum of series (-1)/(2n-1)!

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