Conquering the Infinity Limit: Integrals and Exponential Functions

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lim_{x\rightarrow + ∞} \frac{\int^{x^3}_{0} e^{t^2}dt}{x \int^{x^2}_{0} e^{t^2}dt}


Attempt at a solution: I don't really know where to start. Any hints?
 
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L' Hopital's Rule. Product Rule for the denominator. Fundamental Theorem of Calculus to differentiate the integrals. Don't forget that the bounds are functions of ##x##, so apply Chain Rule (Leibniz's Rule).

After the first step, you'll end up with an expression that I'll call ##L##. Find and simplify ##L^{-1}## with a further application of all those rules. Then deduce what ##L## should be at the limit.
 
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Thanks. When I get home I'll get to work.
 
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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