Method

The root mean square errors

Chebyshev, $N=5$

1.743E-18

Chebyfun

8.664E-18

Runge-Kutta methods, $N=100$ [3]

6.899E-03

Beam function using Galerkin, $N=4$ [1]

0.975E-04

Beam function using Collocation, $N=4$ [2]

0.855E-03