Avoid logging and registration mandates at all cost!There is hundreds of Free on-line calculators at your disposal on the web. There is thousand of free tutorials on-line, design to teach or refresh your math skills.
If you need other calculator programs for your PC, Trisquel has a very good repositories on calculators. If you really need to install from the GNU repositories then visit http://directory.fsf.org/wiki/Main_Page and do a search for it.
