Formula_4317

\[\{\alpha, \beta\}=\frac{1}{2} \int_{-\infty}^{\infty}\left(\frac{\delta \alpha}{\delta u} \frac{\partial}{\partial x} \frac{\delta \beta}{\delta u}-\frac{\delta \beta}{\delta u} \frac{\partial}{\partial x} \frac{\delta \alpha}{\delta u}\right) d x .\]