How to write conditional equations with one-sided curly bracket in TeXmacs

Here is the photo. How to write conditional equations with one-sided curly bracket in TeXmacs?

I tried inserting Equation and Equations. I didn't manage to insert the curly bracket.
In LaTeX, it's like:

\documentclass{article}
\usepackage{amsmath}

\begin{document}
\[
    f(x)= 
\begin{cases}
    \frac{x^2-x}{x},& \text{if } x\geq 1\\
    0,              & \text{otherwise}
\end{cases}
\]
\end{document}

I've solved it by myself.

In equation mode you can click on Insert a table in the tool bar, then choose Choice, grid with with one-sided curly bracket will be automatically generated.

Image here: https://i.sstatic.net/JE1B8.png