LibreOffice 24.8 Help
Here is an example of how to create a matrix with LibreOffice Math. If you want to use the example in your own formula, you can copy it to the Commands window using the clipboard.
font sans bold size *2 A =left[matrix{A_11#A_12#dotsaxis#A_{1n}##A_21#{} #{}#A_{2n}##dotsvert#{}#{}#dotsvert##A_{n1}#A_{n2}#dotsaxis#A_nn}right]