{title2=$\operatorname{Exp}(\lambda)$}
{wiki}

The exponential distribution with rate $c>0$ has density
$$
f(x)=ce^{-cx}\mathbf 1_{\{x\geq0\}}.
$$
It is the gamma distribution with shape one.


Exponential distribution

{wiki=Exponential_distribution}

The Exponential distribution is a continuous probability distribution often used to model the time between events in a Poisson process. This distribution is characterized by its memoryless property, which implies that the probability of an event occurring in the next instant is independent of how much time has already elapsed.


 Exponential distribution

ID: exponential-distribution