Math & Science ⇒ Preventing autosized brackets from including underbraces

[CaptainProton]

How can I prevent the autosized brackets from including the underbrace in the following example?

Code: Select all

\documentclass{scrreprt}
\usepackage{amsmath}
\begin{document}
 \begin{align*}
    s \in \left[\underbrace{b - b \sqrt{1 + \frac{1}{\gamma}}}_{< 0}; \quad b + b \sqrt{1 + \frac{1}{\gamma}}\right].
  \end{align*}
\end{document}

\Bigg-brackets are not large enough

[Stefan Kottwitz]

You could set the hight to zero by smash and insert an invisible \rule to get a certain height:

Code: Select all

\documentclass{scrreprt}
\usepackage{amsmath}
\begin{document}
\begin{align*}
    s \in \left[\rule{0pt}{16pt}\smash{\underbrace{b - b \sqrt{1 + \frac{1}{\gamma}}}_{< 0}; \quad b + b \sqrt{1 + \frac{1}{\gamma}}}\right].
  \end{align*}
\end{document}

Stefan

[localghost]

[...] \Bigg-brackets are not large enough

Somehow I don't see this problem (see attachment).

Code: Select all

\documentclass{scrreprt}
\usepackage{amsmath}

\begin{document}
  \begin{align*}
    s\in\Biggl[\underbrace{b-b\sqrt{1+\frac{1}{\gamma}}}_{< 0}\; ; \; b+b\sqrt{1+\frac{1}{\gamma}}\Biggr].
  \end{align*}
\end{document}

A variation of Stefan's idea could look like shown below. But I think it's not as satisfying as the example above.

Code: Select all

\documentclass{scrreprt}
\usepackage{amsmath}

\begin{document}
  \begin{align*}
    s\in\left[\smash{\underbrace{b-b\sqrt{1+\frac{1}{\gamma}}}_{< 0}}\; ; \; b+b\sqrt{1+\frac{1}{\gamma}}\right].
  \end{align*}
\end{document}

In opposite to Stefan I only "hide" the size of the part with the brace. So I don't need this invisible strut.


Thorsten

[CaptainProton]

Somehow I don't see this problem (see attachment).

Yes, you're right, the \Bigg brackets are okay here. Originally I use the fourier package where they are not large enough. I should have checked that before and included it in the mwe.

A variation of Stefan's idea could look like shown below. But I think it's not as satisfying as the example above.

That looks okay for me. Thanks to you both.