Bernoulli 1696 challenge: curve of fastest descent under gravity is cycloid x = R(θ - sin θ), y = R(1 - cos θ). Solved by Newton, Leibniz, l'Hôpital. Founding problem of calculus-of-variations; Snell's-law analogy.
Bernoulli 1696 challenge: curve of fastest descent under gravity is cycloid x = R(θ - sin θ), y = R(1 - cos θ). Solved by Newton, Leibniz, l'Hôpital. Founding problem of calculus-of-variations; Snell's-law analogy.