The finite-domain wave equation up = Upr, with c = 1 and boundary conditions u (0, () = u(27, t) =0 has the solution u(r, t) = E (2k)2 sin([2k - 1]r) sin([2k1]t) Find a point r* in within the interval (0, 2x) where u(r*, () =0 for all time. Such points in space are called nodal points where the solution is stationary