[Maxima] find_root with bfloats

[Robert Dodier]

Kostas, you must replace all of the ordinary floating point
arithmetic with Maxima arithmetic.
(There may be a way to get Lisp to call the appropriate
arithmetic functions automatically but, if so, I don't know how
to do that.)

You can translate arithmetic as follows:

 Lisp  Maxima

 +  m+
 *  m*
 -  m-
 /  m//

 >  mgrp
 <  not mgqp
 >= mgqp
 <= not mgrp
 = like

HTH

Robert Dodier