# derivative of vector using prime symbol [duplicate]

The problem is shown on the picture. I want to use prime symbol for derivative of vector, but as you can see, it doesn't look well (prime symbol and vector arrow are 'glued' together). What would be the easiest way to fix it?

## marked as duplicate by egreg, Steven B. Segletes, LaRiFaRi, Manuel, Maarten DhondtJul 1 '15 at 12:52

• I would just add \, before the prime. This could be achieved in a macro with \def\primevec#1{\vec#1\,'} – Steven B. Segletes Jul 1 '15 at 12:28
• Apparently, this is angular momentum and the relevant derivative is respect to time, not space, so a dot should be used instead of a prime, from a Physicist's view – user31729 Jul 1 '15 at 12:41

From a Physicist's view I suggest both the usage of esvect (font) package and \dot instead of primes, since the relevant equation contains a time derivative.

The esvect provides distinctive vector arrows, the relevant command is \vv instead of \vec, however.

\documentclass{article}

\usepackage{amsmath}
\usepackage{esvect}

\newcommand{\dotvec}[1]{\dot{\vv{#1}}}

\begin{document}

$\vv{h} = \vv{r} \times \vv{v} = \vv{r} \times \dotvec{r}$

\end{document}