ABSTRACT
The partial derivative of the Lagrangian F(x,y,v) with respect to v, F,v (x,y,v) or F,y′ (x,y,y′), has played an important role in the development of the theory of the calculus of variations up to this point. It enters into the Euler–Lagrange equation and both Erdmann corner conditions as well as Euler boundary conditions and transversality conditions. Traditionally, mathematicians, scientists and engineers have found it convenient to give it a separate label by setting. () p = F , y ′ ( x , y , y ′ ) . https://s3-euw1-ap-pe-df-pch-content-public-p.s3.eu-west-1.amazonaws.com/9780203749821/5a9bd1b0-aa97-4dfe-adb3-8f69a65a6308/content/eq1194.tif"/>
