Sum of series 4x

The solution

You have entered [src]

  oo     
 __      
 \ `     
  )   4*x
 /_,     
n = 2

$$\sum_{n=2}^{\infty} 4 x$$

Sum(4*x, (n, 2, oo))

The radius of convergence of the power series

Given number:
$$4 x$$
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
$$a_{n} = 4 x$$
and
$$x_{0} = 0$$
,
$$d = 0$$
,
$$c = 1$$
then
$$1 = \lim_{n \to \infty} 1$$
Let's take the limit
we find

True

False

The answer [src]

oo*x

$$\infty x$$

oo*x

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```
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Newton–Mercator series
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```
Exam the series for convergence
```
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```

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Sum of series 4x

The solution

Examples of finding the sum of a series