A differential equation of the form
where $\phi$ and $f$ are the functions to be differentiated; first studied in 1748 by J. d'Alembert. Also known as the Lagrange equation.
|[a1]||E.L. Ince, "Integration of ordinary differential equations" , Oliver & Boyd (1963) pp. 43ff|
D'Alembert equation. Encyclopedia of Mathematics. URL: http://www.encyclopediaofmath.org/index.php?title=D%27Alembert_equation&oldid=32805