How do you evaluate the integral $int e^-xdx$ from 0 to $oo$ ?

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Answer 1 · 2016-07-19T13:32:30

1

$int_0^oo e^-x \ dx$

$= int_0^oo -d/dx (e^-x) \ dx$

$= int_oo^0 d/dx (e^-x) \ dx$

$= [ e^-x ]_oo^0$

$=1 - 0 = 1$

How do you evaluate the integral int e^-xdxint e^-xdx from 0 to oooo?