Global Estimates for Mixed Methods for Second Order Elliptic Equations
نویسندگان
چکیده
Global error estimates in L2(Q), L°°(Q), and H~S(Q), Q in R2 or R3, are derived for a mixed finite element method for the Dirichlet problem for the elliptic operator Lp = -div(a grad p + bp) + cp based on the Raviart-Thomas-Nedelec space V^ X Wh c H(div; Í2) X L2(ü). Optimal order estimates are obtained for the approximation of p and the associated velocity field u = -(a grad p + bp) in L2(fl) and H~S(Q), 0 < s < k + 1, and, if ß c R2, for/? in L°°(Q)..
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