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Sum of series log(2*x+1)



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The solution

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  oo              
 __               
 \ `              
  )   log(2*x + 1)
 /_,              
n = 1             
n=1log(2x+1)\sum_{n=1}^{\infty} \log{\left(2 x + 1 \right)}
Sum(log(2*x + 1), (n, 1, oo))
The radius of convergence of the power series
Given number:
log(2x+1)\log{\left(2 x + 1 \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=log(2x+1)a_{n} = \log{\left(2 x + 1 \right)}
and
x0=0x_{0} = 0
,
d=0d = 0
,
c=1c = 1
then
1=limn11 = \lim_{n \to \infty} 1
Let's take the limit
we find
True

False
The answer [src]
oo*log(1 + 2*x)
log(2x+1)\infty \log{\left(2 x + 1 \right)}
oo*log(1 + 2*x)

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