[Tex/LaTex] Laplace’s Equation Symbol

greeksymbols

I used \nabla to present the laplace equation but it doesn't work, is there any method to write the del operator (Gradient) symbol?

Best Answer

here an example:

\documentclass[border=10mm]{standalone}
\begin{document}
\begin{equation}
    \nabla (fg)= f\nabla g + g \nabla f
\end{equation}

\end{document}

it yields:

enter image description here

if this does not work there must e something wrong with your TeX installation.

Related Solutions

[Tex/LaTex] Correct symbol for the Laplace operator ($\Delta$)

If you use the D'Alembert operator as well, you might find pretty using the symbol \bigtriangleup for your Laplace operator, in order to get a similar look as the \Box symbol that is being used for D'Alambertian. In the following, a tricky construction with \mathop and \mathbin is used to get the proper spacing:

\documentclass{article}

\usepackage{amsmath,amssymb}

\newcommand*\Laplace{\mathop{}\!\mathbin\bigtriangleup}
\newcommand*\DAlambert{\mathop{}\!\mathbin\Box}

\pagestyle{empty}

\begin{document}

\begin{gather*}
  \phi(1+\Laplace A) \neq \phi(1+\Delta A)
\\ 
  \phi(1+\DAlambert A) \neq \phi(1+\Laplace A)
\\ 
  f\Laplace g
\end{gather*}

\end{document}

Example

[Tex/LaTex] email symbol while using package listings

You have to tell listings and \verb to change the @ into \MVAt:

\documentclass{article}
\usepackage{marvosym,listings,etoolbox}

\lstset{literate={@}{\MVAt}1}

\patchcmd{\verb}{\dospecials}{\dospecials\atspecial}{}{}
\def\atspecial{\begingroup\lccode`~=`@
  \lowercase{\endgroup\let~}\MVAt
  \catcode`@=\active}

\begin{document}
\begin{lstlisting}[framexleftmargin=0mm,
                   basicstyle=\ttfamily\small,
                   breaklines,
                   columns=fullflexible]
' having 1=1--
' or 1 in (select @@version)--
' union all select @@version--
' OR 'unusual' = 'unusual'
' OR 'something' = 'some'+'thing'
\end{lstlisting}

\verb|declare @s varchar(8000)|
\end{document}

There's no need to use \ttfamily around \verb.