Latex format

\begin{bmatrix}1&0\\3&4\end{bmatrix} \(\textrm{how to format matrixes: }\begin{bmatrix}1&0\\3&4\end{bmatrix}\)

\underbrace: Use \underbrace{text-above}_{text-below} \(\underbrace{text-above}_{text-below}\)

\underset: Use \underset{text-below}{text-above} \(\underset{text-below}{text-above}\)

\Biggr \biggr \(\displaystyle|_{x}^{y}\biggr|_{x}^{y}\Biggr|_{x}^{y}\)

\displaystyle \(\int_{x}^{y}\frac{x}{y}\) / \(\displaystyle\int_{x}^{y}\frac{x}{y}\)

\cancel \(\cancel{69}\)

\DeclareMathOperator\newcommandhere{newcommandhere}