Talk:Topkis's theorem

In example, Topkis's theorem uses differentiability too
The example states that the problem with the implicit function theorem is that it assumes the objective is twice (continuously) differentiable. However, the analysis using Topkis's theorem also uses the fact that the objective is twice differentiable. Could someone present a more compelling example? LachlanA (talk) 04:34, 17 July 2009 (UTC)