This is an inline math expression: $\frac{-b\pm\sqrt{{{b}^{2}}-4ac}}{2a}$.

This is displayed:

\[\begin{matrix} 1 & 2 & \phi  & \pi   \\   \theta  & \beta  & \sqrt{2} & \partial x \\ a\otimes b & \lambda  & \Gamma  & {{\pi }^{2}}  \\ 4! & \Xi  & \Delta y & -3  \\ \end{matrix}\]