# Label terms of LaTeX equation [duplicate]

I'm interested in labelling my latex equation, by giving the physical phenomenon contributing to the term. For instance x = f(y) + g(y). So a horizontal curly bracket to explain that f(y) is derived from some phenomenon, say resistance and g(y) is derived some other phenomenon, say gravity.

How can I give a name to f(y) as resistance and g(y) as gravity in the equation? Hope I'm able to explain my intentions.

## marked as duplicate by Francis, user13907, Jesse, Maarten Dhondt, Svend TveskægDec 22 '15 at 11:44

You have \underbrace from amsmath and \underbracket from mathtools (which loads amsmath). I added some horizontal adjustment with the \clap command (from mathtools), since the labelled terms are short:

\documentclass{article}

\usepackage{mathtools}

\begin{document}

$x = \underbracket[0.8pt]{f(y)}_\text{\clap{resistance~}} + \underbracket[0.8pt]{g(y)}_\text{\clap{~gravity}}$
$x = \underbrace{f(y)}_\text{\clap{resistance~}} + \underbrace{g(y)}_\text{\clap{~gravity}}$%%

\end{document}


Using the amsmath package, you can do this as follows:

\documentclass{article}

\usepackage{amsmath}

\begin{document}

$x = \underbrace{f(y)}_{\text{resistance}} + \underbrace{g(y)}_{\text{gravity}}$

\end{document}


This yields: