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  • Sum of series:
  • 15 15
  • cos(x+y)
  • 1/(x*ln(x)^2)
  • 1/((3n-2)*(3n+1)) 1/((3n-2)*(3n+1))
  • Integral of d{x}:
  • 1/(x*ln(x)^2) 1/(x*ln(x)^2)
  • Graphing y =:
  • 1/(x*ln(x)^2)
  • Identical expressions

  • one /(x*ln(x)^ two)
  • 1 divide by (x multiply by ln(x) squared )
  • one divide by (x multiply by ln(x) to the power of two)
  • 1/(x*ln(x)2)
  • 1/x*lnx2
  • 1/(x*ln(x)²)
  • 1/(x*ln(x) to the power of 2)
  • 1/(xln(x)^2)
  • 1/(xln(x)2)
  • 1/xlnx2
  • 1/xlnx^2
  • 1 divide by (x*ln(x)^2)

Sum of series 1/(x*ln(x)^2)



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The solution

You have entered [src]
  oo           
____           
\   `          
 \        1    
  \   ---------
  /        2   
 /    x*log (x)
/___,          
n = 2          
n=21xlog(x)2\sum_{n=2}^{\infty} \frac{1}{x \log{\left(x \right)}^{2}}
Sum(1/(x*log(x)^2), (n, 2, oo))
The radius of convergence of the power series
Given number:
1xlog(x)2\frac{1}{x \log{\left(x \right)}^{2}}
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=1xlog(x)2a_{n} = \frac{1}{x \log{\left(x \right)}^{2}}
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   
---------
     2   
x*log (x)
xlog(x)2\frac{\infty}{x \log{\left(x \right)}^{2}}
oo/(x*log(x)^2)

    Examples of finding the sum of a series