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Sum of series/ 1/n(n-1)

Sum of series 1/n(n-1)

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n = 2

\sum_{n=2}^{\infty} \frac{n - 1}{n}

Sum((n - 1)/n, (n, 2, oo))

The radius of convergence of the power series

Given number:

\frac{n - 1}{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{n - 1}{n}

and

x_{0} = 0

d = 0

c = 1

then

1 = \lim_{n \to \infty}\left(\frac{\left(n + 1\right) \left|{n - 1}\right|}{n^{2}}\right)

True

False

The rate of convergence of the power series

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oo

\infty

oo

Numerical answer

The series diverges

The graph