Proving Divergence of Alternating Series with Limit Comparison Test

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Dell
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how do i prove that the following series diverges?

\sum(-1)n-1*\frac{n-1}{n+1}*(1/\sqrt[n]{n})

is it enough to say that

lim {n->inf} \frac{n-1}{n+1}*(1/\sqrt[n]{n}) is not 0 ?


i know for regular series this would be okay but what about series with alternating signs??

how else can i tbe proven??
 
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Yes, an alternating series converges if and only if the limit of the terms go to zero.
 
thanks, youve really helped me with this work,
 
Prove $$\int\limits_0^{\sqrt2/4}\frac{1}{\sqrt{x-x^2}}\arcsin\sqrt{\frac{(x-1)\left(x-1+x\sqrt{9-16x}\right)}{1-2x}} \, \mathrm dx = \frac{\pi^2}{8}.$$ Let $$I = \int\limits_0^{\sqrt 2 / 4}\frac{1}{\sqrt{x-x^2}}\arcsin\sqrt{\frac{(x-1)\left(x-1+x\sqrt{9-16x}\right)}{1-2x}} \, \mathrm dx. \tag{1}$$ The representation integral of ##\arcsin## is $$\arcsin u = \int\limits_{0}^{1} \frac{\mathrm dt}{\sqrt{1-t^2}}, \qquad 0 \leqslant u \leqslant 1.$$ Plugging identity above into ##(1)## with ##u...

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