MHB Is the Product of Integrable Functions also Integrable?

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The discussion revolves around the integrability of the product of two functions, h and g, defined on different spaces X and Y. It poses a problem requiring proof that if the product function f(x,y) = h(x)g(y) is integrable on the product space X×Y, then the integral of f with respect to the product measure equals the product of the integrals of h and g. The thread notes that the measures μ and ν do not need to be σ-finite for the proof to hold. No solutions have been provided yet, and the original poster is currently focused on preparing for the GRE. The topic remains open for further discussion and solutions.
Chris L T521
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Here's this week's problem!

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Problem
: Let $h$ and $g$ be integrable functions on $X$ and $Y$, and define $f(x,y)=h(x)g(y)$. Show that if $f$ is integrable on $X\times Y$ with respect to the product measure, then
\[\int_{X\times Y} f\,d(\mu\times\nu) = \int_X h\,d\mu \int_Y g \,d\nu.\]

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Note: We do not need to assume that $\mu$ and $\nu$ are $\sigma$-finite.

Remember to read the http://www.mathhelpboards.com/showthread.php?772-Problem-of-the-Week-%28POTW%29-Procedure-and-Guidelines to find out how to http://www.mathhelpboards.com/forms.php?do=form&fid=2!
 
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No one answered this week's problem. I don't have a solution ready at this time; it's on my backlog of solutions to write and I'll try to get them done soon. I take the GRE on Saturday so it's been crunch time for me. Thank you for your patience!