Is a series is convergent or divergent

Littlemin5
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Homework Statement


Determine the convergence or divergence of the series. If the series is convergent, find its sum. Justify each answer.

(n=1, to infinity) \sum(7/9 + n^5)

Help please? I missed a lot of school recently from being sick and need help with this!
 
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For clarification, do you mean

\sum_{n=1}^{\infty}\frac{7}{9 + n^5}

or do you mean

\sum_{n=1}^{\infty}(\frac{7}{9} + n^5)
 
Try adding up the first few terms. What do you get?
 
jgens said:
For clarification, do you mean

\sum_{n=1}^{\infty}\frac{7}{9 + n^5}

or do you mean

\sum_{n=1}^{\infty}(\frac{7}{9} + n^5)

sorry I meant:

\sum_{n=1}^{\infty}\frac{7}{9 + n^5}
 
Thanks for the clarification. Alright, what have you tried so far?
 
jgens wants you think think about a comparison test, I'm very sure.
 
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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