numerical methods gone missing?



numerical methods gone missing?

I am trying to help someone on the freenode #maximia IRC channel, they would
like to use the find_root function as documented in in the Maximia manual.

However, any attempt to use the function, such as

find_root (sin(x) - x/2, x, 0.1, %pi);

fails by returning a slightly modified version of itself, basically the
output is
find_root (sin(x) - x/2, x, 0.1, %pi);
with some minor formatting changes.
In the manuals example the result should have been

1.895494267033981

I suspect that we do not have the proper numerical module loaded? I tried
loading a bunch of stuff out of /usr/share/maxima/5.9.1, and it failed to
fix the problem.

What must we do to get the find_root function to work as advertised.

Thank you for your time,
James Supancic