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  • Sum of series:
  • x^n/n
  • 1/n! 1/n!
  • nx^n!
  • (x-4)^n/sqrt(n)
  • Identical expressions

  • (x- four)^n/sqrt(n)
  • (x minus 4) to the power of n divide by square root of (n)
  • (x minus four) to the power of n divide by square root of (n)
  • (x-4)^n/√(n)
  • (x-4)n/sqrt(n)
  • x-4n/sqrtn
  • x-4^n/sqrtn
  • (x-4)^n divide by sqrt(n)
  • Similar expressions

  • (x+4)^n/sqrt(n)

Sum of series (x-4)^n/sqrt(n)



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The solution

You have entered [src]
  oo          
____          
\   `         
 \           n
  \   (x - 4) 
   )  --------
  /      ___  
 /     \/ n   
/___,         
n = 1         
$$\sum_{n=1}^{\infty} \frac{\left(x - 4\right)^{n}}{\sqrt{n}}$$
Sum((x - 4)^n/sqrt(n), (n, 1, oo))
The radius of convergence of the power series
Given number:
$$\frac{\left(x - 4\right)^{n}}{\sqrt{n}}$$
It is a series of species
$$a_{n} \left(c x - x_{0}\right)^{d n}$$
- power series.
The radius of convergence of a power series can be calculated by the formula:
$$R^{d} = \frac{x_{0} + \lim_{n \to \infty} \left|{\frac{a_{n}}{a_{n + 1}}}\right|}{c}$$
In this case
$$a_{n} = \frac{1}{\sqrt{n}}$$
and
$$x_{0} = 4$$
,
$$d = 1$$
,
$$c = 1$$
then
$$R = 4 + \lim_{n \to \infty}\left(\frac{\sqrt{n + 1}}{\sqrt{n}}\right)$$
Let's take the limit
we find
$$R = 5$$

    Examples of finding the sum of a series