# Change the equation font locally

I want to change the equation font to mathbf in a single equation environment, equation or align.

How do I do that? I tried

\begin{align}
\begin{mathbf}
equation1 \\
equation2
\end{mathbf}
\end{align}


and

\begin{align}
\mathbf{
equation1 \\
equation2
}
\end{align}


with no luck. It seems as if \\ breaks the \mathbf environment..?

-

For making a complete environment bold, you could use the switch \boldmath. \unboldmath switches back.

\boldmath
\begin{align}
ax + by + c &= 0 \\
ax - by &= xy
\end{align}
\unboldmath


If \bf is available (base classes still define it), \everymath{\bf} before the align environment switches to the \mathbf font for the complete environment. Of course it could be done without \bf, but it would be the quickest way.

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Thanks for your input! It's definitely an option, but it's not quite the same as mathbf. Your solution sets the equation in bold AND italic, which mathbf doesn't. – 0sh Jan 8 '11 at 18:28
@mewoshh: Ok, I focussed on bold - but mathbf is possible, I'lledit. – Stefan Kottwitz Jan 8 '11 at 18:56
@Stefan: \everymath{\bf} also effects footnotes – Herbert Jan 8 '11 at 19:18
@Stefan: btw - what if instead of mathbf I want to use any other of the math fonts, for instance mathtt? Can't use mathbold or bf here - there must be a way to use math* in the environment..? – 0sh Jan 8 '11 at 20:03
@Herbert: I know, but footnotes should not be used within a math environment, and after it I would disable this setting. I didn't mean to use \everymath simply globally because of such side effects. – Stefan Kottwitz Jan 8 '11 at 21:08