Proof: Integral is finite (Fubini/Tonelli?)

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Homework Statement


Let f:[0,1]→ℝ be non-negative and integrable. Prove that \int_{[0,1]}\frac{f(y)}{|x-y|^{1/2}}dy is finite for ae x in [0,1]

Homework Equations


This looks like a Fubini/Tonelli's Theorem problem from the problem givens.

The Attempt at a Solution


I honestly don't know where to start with this problem. Any help or gentle nudges would be appreciated.
 
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It doesn't seem to me to be true, so I must be missing something.
Given x in (0, 1), consider ##f(y) = |x-y|^{-\frac{1}{2}}## for y≠x, f(x)=0. Isn't that integrable? But ##\int_0^1|x-y|^{-1}dy## is not finite.
 
Here's what I am thinking.

Consider: \int_{[0,1]}f(y)\left[\int_{[0,1]}\frac{1}{|x-y|^{1/2}}dx\right]dy=\int_{[0,1]}f(y)\left[2\left(\sqrt{1-y}-\sqrt{y}\right)\right]dy\leq\int_{[0,1]}f(y)\cdot 2<∞. Therefore \int_{[0,1]^{2}}\frac{f(y)}{|x-y|^{1/2}}<\infty by Tonelli's Theorem. Then \int_{[0,1]}\frac{f(y)}{|x-y|^{1/2}}dy is finite for ae x in [0,1] again by Tonelli.

Think I still need to add some measurability and non-negative qualifiers, but this is close.

Thoughts?
 
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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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