could somebody tell me why I get an error by using the second equation in the added lyx-file?I too have always wondered about this.
This is the relevant part of the lyx-file:
\begin_inset Formula R=Rh/2+(ZZ-4)+K_{ab}
The problem seems to be that changing the math font takes lyx out of math mode. What (I think) you should get is;
\begin_inset Formula $\mathrm{R=Rh/2+(ZZ-4)+K_{ab}}$
which works fine if you manually edit the lyx file.
I haven't seen anything in the FAQ or archives but then searching for "math font" problems always leads to another, more frequent FAQ.
Gareth
