Which expansion is used for this result?

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The discussion focuses on the approximation of the expression exp(hv/kT) - 1 when hv is much less than kT, which simplifies to hv/kT. Participants recognize this result as part of the Maclaurin series expansion for the exponential function. The conversation highlights the importance of understanding various expansions, particularly in the context of physics and thermodynamics. A link to a resource on Maclaurin series is shared for further reference. Overall, the thread emphasizes the relevance of mathematical expansions in scientific applications.
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exp (hv/kT) - 1



For hv<<kT



exp (hv/kT) - 1 is approximately equal to hv/kT


thanks for any ideas.
 
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How many expansions do you know?

exp(x) ~ 1+x should look familiar.
 

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