## 2. Rayleigh-Ritz procedure (cont'd)

 A functional is a function of a function. An admissible function is one which satisfies the boundary conditions, as well as certain continuity conditions.

The procedure is based on the theorem of minimum potential energy in mechanics: if one has a functional giving the potential energy of a system, then the ‘admissible’ function which minimizes that functional is the solution of the system.

R. Funnell