A system with Lagrangian L = L(q, q̇) and canonical momentum p = ∂L/∂q̇ exhibits a primary constraint ψ (p, q) = 0. If u(p, q) is an arbitrary function, show that the Lagrange equation and the primary constraint together imply Hamilton’s equations for a “primary Hamiltonian”, H_P = H + uψ. Compare the total differentials of H and ψ.