# Inserting braces in a brace [closed]

I don’t know how can I ensert the right braces using latex...

Any help is appreciated... • That seems to be a question for TeX - LaTeX, rather than this meta. – Asaf Karagila Jan 16 '19 at 15:38
• A fairly tedious way to do it would be using nested "array" expressions. – hardmath Jan 16 '19 at 15:41

Here's an approach, using the cases environment for the left side brace and some array environments to group and brace on the right hand side:
$$\begin{cases} \left. \begin{array}{l} \frac{dG(t)}{dt} = G_{in} - \sigma_2 G - a\left(c+ \frac{mI}{n+I} \right)G + b \\ \frac{dI(t)}{dt} = \frac{\sigma_1 G^2}{\alpha_1^2 + G^2} - d_i I(t) \end{array} \right\} & , \;\;\; G\lt L_G \text{ or } I\gt I_C, \\ \left. \begin{array}{l} G(t^+) = G(t) \\ I(t^+) = I(t) + \sigma \end{array} \right\} & , \;\;\; G = L_G \text{ and } I\le I_C, \end{cases}$$
Note that the cases environment itself could be similarly replaced by using an array environment plus adaptive bracing. The idea was suggested in this note about the "cases" package.
• @JyrkiLahtonen: I think you are right about the difficulty of aligning the equations across the cases boundaries. A naive use of the align* environment apparently produces an error message about nested equation structures. – hardmath Jan 17 '19 at 15:51
• example:$$\left\{{\left.{case1\\[6px]case2} \right\}\\[6px]\left.{case3\\[6px]case4}\right\}}\right.$$ okay maybe a case environment would be better – user645636 Jun 8 '19 at 10:21