We establish a new energy inequality for the difference of two semiconvex functions in a bounded open convex set D of RnR^n. This inequality is applied to the L2L^2-approximation problem of the gradient of the unknown solution of the nonlinear elliptic partial differential equation provided that the latter solution is a semiconvex function in D.

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Kakha Shashiashvili

I. Javakhishvili Tbilisi State University, Faculty of Exact and Natural Sciences, 2 University Street, Tbilisi 0186, Georgia

Malkhaz Shashiashvili

A. Razmadze Mathematical Institute, I. Javakhishvili Tbilisi State University, 2 University Street, Tbilisi 0186, Georgia

mshashiashvili@yahoo.com
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K. Shashiashvili, M. Shashiashvili. “From the Uniform Approximation of a Solution of the PDE to the L^2-Approximation of the Gradient of the Solution.” Journal of Convex Analysis 21 (2014), No. 1, 237–252. https://doi.org/10.68381/jca21013