where H1
0 () is the Sobolev space of functions in L2() whose derivatives are also squareintegrable,
and with vanishing function values on , and u denotes the first variation of u.
In finite element and meshfree Galerkin methods, u(x) is approximated by uh(x) (belongs to a
finite-dimensional subspace of H1
0 ()) of the form given in Equation (1). A similar approximation
is used for the test function u. Since the nodal coefficients that appear in uh are arbitrary,