1

Using a bold \Box symbol from the amssymb package leads to a strange output showing three consecutive bold box symbols of decreasing size when breqn package was loaded. This effect appears with the \bm{} command of the bm package as well as \boldsymbol{} from amssymb. MWE:

\documentclass[]{article}  

\usepackage{amssymb}        % Math symbols
\usepackage{bm}                 % Access bold symbols in maths mode
\usepackage{breqn}      % Automatic line-breaking of displayed math expressions

\begin{document}

$\Box$\\
$\bm{\Box}$\\
$\boldsymbol{\Box}$

\end{document}

Output without breqn:

Ouput with breqn package loaded:

1

Double embrace the \Box will allow compilation, though I can't say the boxes are emboldened. What was goal? Bold boxes, or mere compilation? For bold boxes, see Workaround below.

\documentclass[]{article}  

\usepackage{amssymb}        % Math symbols
\usepackage{bm}                 % Access bold symbols in maths mode
\usepackage{breqn}      % Automatic line-breaking of displayed math expressions

\begin{document}

$\Box$\\
$\bm{{\Box}}$\\
$\boldsymbol{{\Box}}$

\end{document}

WORKAROUND:

Use \fakebold for the box:

\documentclass[]{article}  

\usepackage{amssymb}        % Math symbols
\usepackage{bm}                 % Access bold symbols in maths mode
\usepackage{breqn}      % Automatic line-breaking of displayed math expression
\usepackage{scalerel}
\newlength\bshft
\bshft=.25pt\relax
\def\fakebold#1{\ThisStyle{\ooalign{\raisebox{\bshft}{$\SavedStyle#1$}\cr%
  \kern-\bshft$\SavedStyle#1$\cr%
  \kern\bshft$\SavedStyle#1$}}}
\begin{document}

$\Box$\\
$\fakebold{\Box}$\\

\end{document}

enter image description here

| improve this answer | |

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.