Find the response of a simple pendulum numerically by solving the nonlinear equation: [ddot{theta}+frac{g}{l}left(theta-frac{theta^{3}}{6} ight)=0] with (frac{g}{l}=0.01)

Find the response of a simple pendulum numerically by solving the nonlinear equation:

\[\ddot{\theta}+\frac{g}{l}\left(\theta-\frac{\theta^{3}}{6}\right)=0\]

with \(\frac{g}{l}=0.01\) and plot the response, \(\theta(t)\), for \(0 \leq t \leq 150\). Assume the initial conditions as \(\theta(t=0)=\theta_{0}=1 \mathrm{rad}\) and \(\dot{\theta}(t=0)=\dot{\theta}_{0}=1.5 \mathrm{rad} / \mathrm{s}\). Use the MATLAB function ode23 for numerical solution.