Difference between revisions of "Exponential integral E"
From specialfunctionswiki
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The exponential integrals are | The exponential integrals are | ||
| − | $$\mathrm{Ei}( | + | $$\mathrm{Ei}(z) = \int_{-\infty}^x \dfrac{e^t}{t} dt; |\mathrm{arg}(-z)|<\pi$$ |
and | and | ||
| − | + | The exponential integral is related to the [[logarithmic integral]] by the formula | |
| − | |||
$$\mathrm{li}(x)=\mathrm{Ei}( \log(x)).$$ | $$\mathrm{li}(x)=\mathrm{Ei}( \log(x)).$$ | ||
Revision as of 21:00, 4 October 2014
The exponential integrals are $$\mathrm{Ei}(z) = \int_{-\infty}^x \dfrac{e^t}{t} dt; |\mathrm{arg}(-z)|<\pi$$ and The exponential integral is related to the logarithmic integral by the formula $$\mathrm{li}(x)=\mathrm{Ei}( \log(x)).$$
