Difference between revisions of "Ei(x)=-Integral from -x to infinity of e^(-t)/t dt"
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(Created page with "==Theorem== The following formula holds: $$\mathrm{Ei}(-x) = -\displaystyle\int_x^{\infty} \dfrac{e^{-t}}{t} \mathrm{d}t,$$ where $\mathrm{Ei}$ denotes the exponential integ...") |
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==Proof== | ==Proof== | ||
| − | ==References= | + | ==References== |
* {{PaperReference|On certain definite integrals involving the exponential-integral|1881|James Whitbread Lee Glaisher|prev=Exponential integral Ei|next=Exponential integral Ei series}} | * {{PaperReference|On certain definite integrals involving the exponential-integral|1881|James Whitbread Lee Glaisher|prev=Exponential integral Ei|next=Exponential integral Ei series}} | ||
[[Category:Theorem]] | [[Category:Theorem]] | ||
[[Category:Unproven]] | [[Category:Unproven]] | ||
Revision as of 03:30, 17 March 2018
Theorem
The following formula holds: $$\mathrm{Ei}(-x) = -\displaystyle\int_x^{\infty} \dfrac{e^{-t}}{t} \mathrm{d}t,$$ where $\mathrm{Ei}$ denotes the exponential integral Ei and $e^{-t}$ denotes the exponential.
