BRACHISTOCHRONE
http://dmentrard.free.fr/GEOGEBRA/Maths/Export5/BrachMD.html
[url=http://dmentrard.free.fr/GEOGEBRA/Maths/Export5/BrachMD.html]http://dmentrard.free.fr/GEOGEBRA/Maths/Export5/BrachMD.html[/url]
Information: BRACHISTOCHRONE