Solution
= Solution
Taylor expansion gives $\Gamma_9u=h^2\Delta u+(h^4/12)\Delta^2u+O(h^6)=h^2f+(h^4/12)\Delta f+O(h^6)$. Thus the local residual is $O(h^4)$.
= Solution
Taylor expansion gives $\Gamma_9u=h^2\Delta u+(h^4/12)\Delta^2u+O(h^6)=h^2f+(h^4/12)\Delta f+O(h^6)$. Thus the local residual is $O(h^4)$.