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ChrisVer
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Homework Statement
I am trying to evuluate the value of the integral:
[itex] J= \int_{0}^{∞} \frac{x^{3}}{e^{x}-1}dx[/itex]
Could you please supply me with the method used for that? I thought of breaking the integral from 0 to 1 and from 1 to infinity. That way I could expand the exponential to taylor series for the small values of x, while the second would drop the 1 from the denominator, so it would be like exp[-x]x^3...(am I correct in the idea?).. However with that idea I'm left with a singularity at point 0. Would that mean I need to expand to Laurent series?
(it's not "really" homework, I am just playing around with black body radiation and radiation energy density to show that p[rad]~T^4 which we were given in class).
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