Is Sequence xn Unbounded? Quickest Solution

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Homework Statement


Is the sequence xn=[(n5+7n+3)7]/[(7-n4)6] bounded?


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The Attempt at a Solution



I've managed to tell that the sequence is not bound because as n tends to ∞ xn also tends to ∞ but it took me a relatively long time.
Is there any way of telling this by just looking at the exponents or what is the quickiest way to tell that this sequence will get infinitely large.
 
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gottfried said:

Homework Statement


Is the sequence xn=[(n5+7n+3)7]/[(7-n4)6] bounded?


]



The Attempt at a Solution



I've managed to tell that the sequence is not bound because as n tends to ∞ xn also tends to ∞ but it took me a relatively long time.
Is there any way of telling this by just looking at the exponents or what is the quickiest way to tell that this sequence will get infinitely large.

The highest degree of n in the numerator is 35 and in the denominator is 24. That's all you need to know.
 
I was pretty sure it was something simple. Thanks!
 
There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
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