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VariationalD


returns the variational derivative of the integral with respect to , where the integrand f is a function of u, its derivatives, and x.

returns the variational derivative of the multiple integral with respect to , where f is a function of u, its derivatives and the coordinates .

gives a list of variational derivatives with respect to .
Variational derivative for the arc length of a plane curve:
Variational derivative for the Dirichlet integral in two variables:
Needs["VariationalMethods`"]
Variational derivative for the arc length of a plane curve:
In[2]:=
Click for copyable input
Out[2]=
 
Needs["VariationalMethods`"]
Variational derivative for the Dirichlet integral in two variables:
In[2]:=
Click for copyable input
Out[2]=