how do I break an equation when there is \left and \right involved?

I am using an align environment, and at some point I am interested in breaking an equation to the next line. The problem is that this equation includes a \left and 开发者_运维知识库\right, so when I try to break it using \\, I get an error. Any ideas?

For example, the following wouldn't compile:

\begin{align}
\left(4+5+6+ \\
4 + 6 +2 \right)
\end{align}

Thanks.

You can use \right. at the end of the first line and \left. at the beginning of the second line to function as placeholders for the matching \right wihtout any symbol shown.

So exactly like this:

\begin{align}
\left( 4+5+6+ \right. \\
\left. 4 + 6 +2 \right)
\end{align}

Instead of using \left and \right, you can specify the size of the brackets with \Big, \big, \bigg, etc so that you do not have that kind of problem. See this.

The code you've given will be like this:

\begin{align}
\big(4+5+6+ \\
4 + 6 +2 \big)
\end{align}