Solving an Indeterminant Limit Problem with L'Hopital's Rule

Feldoh
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Homework Statement



Find \lim_{x-> \inf} \frac{(8-x)^{200}}{8^{x+2}}*\frac{8^x}{(3-x^2)^{100}}

Homework Equations


The Attempt at a Solution


Simplified to:

\lim_{x-> \inf} \frac{(8-x)^{200}}{64(3-x^2)^{100}}

Indeterminant form, so I suppose L'hopital's, but it doesn't seem very efficient?
 
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Write the first two or 3 highest order terms of the expansions of the numerator and denominator. You'd agree that all lower order terms become increasingly insigificant as x becomes large, right?
 
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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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