I am using overleaf and I am trying to write the following equation into my main text but since it is longer than a line I have to break it into smaller parts and for that I am using the miltline. However, when I am doing that the brackets and parenthesis I used in the first line do not continue to hold for the second line. I read online that the parenthesis should open and close in the same line but if that is not possible I can use the \left. and \right. commands. I've tried to do that too but the size of the parenthesis change (for example I was using big parenthesis and became small).
This is how I am trying to write it:
\begin{multline}
\dot{z} = \left(\frac{\phi_z - \alpha}{\phi_{zz} } \right) \left\{ \delta - \frac{u_P \theta}{u_c(\alpha-\phi_z)}+ \frac{U_P \xi}{U_c} + \beta \left[ \phi_x - \tau + \frac{wm\big(\theta-\xi(\alpha-\phi_z)\big)}{e^{-\rho t} U_c \theta} \\
+ \frac{U_x \big(\theta-\xi(\alpha-\phi_z)\big)}{U_c \theta} \right] + \frac{(\beta - 1) (\phi_z - \alpha)}{\theta} \right\} - \frac{\beta \phi_{zx}}{\phi_{zz}} \left[ \phi(\beta S, z) - \alpha z - c - \tau \beta S \right]
\end{multline}
Any help would be very much appreciated. Thanks in advance.
\biggl(and\biggr). – campa Dec 09 '20 at 19:08