On the validity of Friedrichs’ inequalities
Křížek, M. & Neittaanmäki, P. (1984). On the validity of Friedrichs’ inequalities. Mathematica Scandinavica 54, 17-26. Retrieved from http://www.mscand.dk/article/view/12037/10053
Published inMathematica Scandinavica
© Mathematica Scandinavica, 1984.
A standard proof of Friedrich's second inequality is based on contradiction argumentation. In this paper a direct proof is presented. Moreover, necessary and sufficient conditions for the validity of Friedrichs' first and second inequality are given for plane domains.
PublisherDENMARK Societates Mathematicae