Math & Science ⇒ Is it possible to break lines in »align« environment?

[Yue]

Suppose I have a very long expression under a sum sign, how can I change lines so that it can be on the page?

If I have something like

Code: Select all

\begin{align}
x=\sum_{k}{ \left[ a + b + c + d + e    \right] }
\end{align}

can I somehow make a line change after b? I tried this, but this does not work:

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\begin{align}
x&=\sum_{k}{ \left[ a + b \\
 &+ c + d + e    \right] }
\end{align}

Is this possible at all?

[localghost]

Suppose I have a very long expression under a sum sign, how can I change lines so that it can be on the page? [...]

I don't see a long expression as limit under the sum sign, only a single character. And behind there is a sum as usual. So you should clarify where you exactly want to have a line break.

Your example doesn't work because you need to have always a complete pair of adjusted delimiters. Invisible delimiters can be typeset by using a period instead of the delimiter symbol.

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\left[ \right.
\left. \right]

For some useful tips you can take a look at the »Math mode« document.


Thorsten