Hi Greg,
I understand that you are trying to plot the first three modes of the analytical solution of a second order differential equation. For this, you need to solve the differential equation and obtain the expressions for the modes. Follow the steps below to reach your desired goal:
- Solve the second-order differential equation analytically to obtain the general solution. You can refer to the documentation.
- The general solution of the differential equation can be expressed as a linear combination of the modes, which will give you the first three modes. You can also determine the characteristic equation for this task.
- Once you obtain the three modes, 'plot' them using the plot function.
I hope this solves your query.