You should be able to access the documentation for all the MATLAB functions available on your computer through the ‘Help’ button above the Command Window. If you want to access the documentation for ode45 online, click on that hyperlink to it.
It will be worth asking about the meaning of ‘trajectory’. If you simply want to plot the three solved variables against each other when you get your ODE function working with ode45, then the plot3 function will work. If you need to do a phase-plane plot, then things get interesting. You have to take your solved variables and time vector and plug them back into your ODE function to get the derivatives. The plot3 function works here as well.
