Math & Science ⇒ A system of equations to be aligned to the left?!

[Sam]

Dear All,

I am having a trouble on a small issue that is messing my Latex document.

I am not quite sure why the following equation does not align to the left? even if I change the right to left

Thanks for your help.

\begin{equation}
\left\{
\begin{aligned}
\dot{x}_{1} = x_{2}\\
\dot{x}_{2} = tr1 \cdot x_{2} + tr2 \cdot u_{1} + tr3 \cdot u_{2} + g\\
\dot{x}_{3} = x_{4}\\
\dot{x}_{4} = tr4 \cdot x_{4} + tr5 \cdot u_{1} + tr6 \cdot u_{2}\\
\end{aligned}
\right
\end{equation}

[Stefan Kottwitz]

Hi Sam,

insert & to mark the equal sign where it should be aligned:

Code: Select all

\documentclass{article}
\usepackage{mathtools} 
\begin{document}
\begin{equation}
\left\{
\begin{aligned}
\dot{x}_{1} &= x_{2}\\
\dot{x}_{2} &= tr1 \cdot x_{2} + tr2 \cdot u_{1} + tr3 \cdot u_{2} + g\\
\dot{x}_{3} &= x_{4}\\
\dot{x}_{4} &= tr4 \cdot x_{4} + tr5 \cdot u_{1} + tr6 \cdot u_{2}
\end{aligned}
\right.
\end{equation}

Also the left sides are aligned, next to the big brace.

Stefan