Root test vs. ratio test question

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cue928
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I am doing the following practice problem in prep for an exam:
sum from n=0 to infinity: (3^n)/(n+1)^n
The book says to use the ratio test on it, which I did, but would the root test also apply to this?
 
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cue928 said:
I am doing the following practice problem in prep for an exam:
sum from n=0 to infinity: (3^n)/(n+1)^n
The book says to use the ratio test on it, which I did, but would the root test also apply to this?


Well...

[tex]\sqrt[n]{\frac{3^n}{(n+1)^n}} =[/tex]

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I had initially changed it to be:
(3/(1+n))^n. Applying the nth square root, I got lim n approaches infinity 3/1+n = 0.