deletions | additions       diff --git a/untitled.tex b/untitled.tex  index b6b64df..a7a9f13 100644  --- a/untitled.tex  +++ b/untitled.tex 
...
\end{equation}  where  \begin{equation}  d =  \sqrt{\frac{2}{\pi}}\sigma + \sqrt{\frac{2}{\pi}}\sigma\left[ \exp\left(-\frac{\mu^2}{2\sigma^2}\right) -1\right] + \mu \left[{\rm erf} \left( \frac{\mu}{\sqrt{2}\sigma} \right) - 1\right] \end{equation}