Le forum de XCAS

For the current version() giac 0.9.4 wrongly gives , which is fixed e.g. in giac 1.1.1.

I'm not responsible for updating Xcas online. You should use webxcas for an almost up to date version of giac online. webxcas is a compilation in javascript of giac, it does not require a server to make the computation (unlike sage), you just need the server once to download the javascript code. There is a nice calculator interface for webxcas, it's smartcas:
http://www.calcenstock.fr/smartcas.html

Thank you! I was not aware of webxcas.