Mister Exam

Other calculators


(3n+4)/(n/((n+1)(n+2)))

Sum of series (3n+4)/(n/((n+1)(n+2)))



=

The solution

You have entered [src]
  oo                   
____                   
\   `                  
 \         3*n + 4     
  \   -----------------
   )  /       n       \
  /   |---------------|
 /    \(n + 1)*(n + 2)/
/___,                  
n = 1                  
$$\sum_{n=1}^{\infty} \frac{3 n + 4}{n \frac{1}{\left(n + 1\right) \left(n + 2\right)}}$$
Sum((3*n + 4)/((n/(((n + 1)*(n + 2))))), (n, 1, oo))
The radius of convergence of the power series
Given number:
$$\frac{3 n + 4}{n \frac{1}{\left(n + 1\right) \left(n + 2\right)}}$$
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
$$a_{n} = \frac{\left(n + 1\right) \left(n + 2\right) \left(3 n + 4\right)}{n}$$
and
$$x_{0} = 0$$
,
$$d = 0$$
,
$$c = 1$$
then
$$1 = \lim_{n \to \infty}\left(\frac{\left(n + 1\right)^{2} \left(3 n + 4\right)}{n \left(n + 3\right) \left(3 n + 7\right)}\right)$$
Let's take the limit
we find
True

False
The rate of convergence of the power series
The answer [src]
oo
$$\infty$$
oo
Numerical answer
The series diverges
The graph
Sum of series (3n+4)/(n/((n+1)(n+2)))

    Examples of finding the sum of a series