Limit Problem: Solving (x+2)/(x3+8) without a Calculator

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I can't seem to figure this out, its very simple. I am just unsure as to how to o about it. Could someone please solve it, showing the method. No calculator either. thanks

Lim as x-> -2 ; (x+2) / (x3+8)
 
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Problems like this usually involve factoring the polynomials involved. Try doing that.
 
yeah, like already said, you need to factor the denominator. I assume you are familiar with the sum of cubes:

a^3+b^3=(a+b)(a^2-ab+b^2) this is all you need to factor the denominator.
 
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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