Using the root test find whether the series converges or diverges

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Using the root test find whether the series converges or diverges:

Lim Sin (4/(3n+3)) / Sin (4/(3n))
n-> inf.

I have no idea how to cancel out the sin terms
 
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It looks like you may need to use L'Hospital's Rule since you have 0/0. Do you know if the answer is 1?
 
mattmannmf said:
Using the root test find whether the series converges or diverges:

Lim Sin (4/(3n+3)) / Sin (4/(3n))
n-> inf.

I have no idea how to cancel out the sin terms
Why would you want to use the root test? It looks like you're using the ratio test. As Dustinfls suggests, this one looks ripe for L'Hopital's Rule.
 
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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