# problems with boldsymbol and cmbright

Καλημέρα!

If I use the package cmbright the command \boldsymbol{} does not work for math symbols (e.g. <, +, 45), but only for letters.

1. What is the problem?
2. I don't remember the purpose that I used cmbright. What is it doing and what are the problems of not having it?

The code is below:

\documentclass{article}

\usepackage{mathtools}
\usepackage[english,greek]{babel}
\usepackage[utf8]{inputenc}
\usepackage{cmbright}
\usepackage{kerkis}

\begin{document}

\textbf{\textlatin{some text} κείμενο}

$\boldsymbol{4+y\alpha<89x}$

$4<89x$

\end{document}


Ευχαριστώ εκ των προτέρων!

The problem is that cmbright apparently does not have bold variant of all the symbols. You could use \pmb [1] instead, but then you'd also get poor man's bold for glyph which have a bold variant. The easiest solution is to use the bm package. This will use bold glyphs where available and poor man's bold otherwise. It's important that you load the bm package after loading your math font.

[1] poor man's bold: printing a letter multiple times with slight offset to get a fake bold effect.

\documentclass{article}

\usepackage{mathtools}
\usepackage[english,greek]{babel}
\usepackage[utf8]{inputenc}
\usepackage{cmbright}
\usepackage{kerkis}

\begin{document}

\textbf{\textlatin{some text} κείμενο}

$\bm{4+y\alpha<89x}$

$4<89x$

\end{document}


I made a high-resolution screenshot. It should be easy to spot the poor man's bold.

• 1) If I use the package bm, the command \boldsymbol{} works again!!! Should I use the \bm instead of \boldsymbol{} or are the same? 2) Is any reason to keep the cmbright package? – Kώστας Κούδας Dec 13 '18 at 8:08
• @ΚώσταςΚούδας The bm package redefines \boldsymbol to do the same as \bm. I prefer \bm because it's only three keystrokes. – Henri Menke Dec 13 '18 at 8:09
• @ΚώσταςΚούδας Regarding the cmbirght package, I kept it because it was part of your example. It provides the Computer Modern Bright font, a sans-serif font for text and math. – Henri Menke Dec 13 '18 at 8:11