Laplace-Operator/R^n/Definition/Begriff/Inhalt

Man nennt

${}\triangle u={\frac {\partial ^{2}u}{\partial ^{2}x_{1}}}+{\frac {\partial ^{2}u}{\partial ^{2}x_{2}}}+\cdots +{\frac {\partial ^{2}u}{\partial ^{2}x_{n}}}\,$

die Laplace-Ableitung von ${}u$.