The Calculus of variations is a field of mathematical analysis that uses variations , which are small changes in functions and functional to find maxima and minima of functional; mappings from a set of functions to the real numbers. The Euler-Lagrange differential equation is the fundamental equation of calculus of variation. Leonhard Euler (15 AprilContinue reading "8 Leonhard Euler Quotes (Calculus of variations – The Euler–Lagrange equation)."