All the functionality in Calculus`VariationalMethods` is now available through the newly created Variational Methods Package.
To access functionality from the new Variational Methods Package, load VariationalMethods`:
Version 5.2
This is the first variational derivative of 
:
Version 5.2
![VariationalD[y[x] Sqrt[1 + y'[x]^2], y[x], x]](Files/VariationalMethods.en/legacy_2.gif)