How to Place a Large Bracket on Only One Side in LaTeX
Code
$$
\left. \int {{ 1 } \over { g (u) }} du \right|\_{u = X\_{t}}
$$
$$ \left. \int {{ 1 } \over { g (u) }} du \right|_{u = X_{t}} $$
In large brackets, if one side (left or right) is unnecessary, you can maintain the size while omitting the rendering by using \left., \right..