Use comparison theorem to determine if \int_{0}^{1}\frac{e^{-x}}{\sqrt{x}}~dx

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Homework Statement


The question says use the comparison to determine if ##\int_{0}^{1}\frac{e^{-x}}{\sqrt{x}}dx## converges. What should I compare to?

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The Attempt at a Solution

 
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Hi tm5501987. Try using [ /tex] with a forward slash and no space. \int_{0}^{1}\frac{e^{-x}}{\sqrt{x}}dx
e^{-x} is bounded between 1 and 1/e on [0,1], right?
 
I am lost, not sure how that gets me to something I can compare to.
 
\int_{0}^{1}\frac{e^{-x}}{\sqrt{x}}dx \lt \int_{0}^{1}\frac{1}{\sqrt{x}}dx. Not so?
 
Got it, 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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