3. Consider the second order ODE T+2x+ 5z =0, (a) Solve the ODE subject to the initial conditions z(0) = 1, #(0) = 2, and sketch the result in solution space. (b) Convert the ODE to a first order system, and plot the paths in phase space. Classify any fixed points, explaining your reasoning. [5 marks)] 4. Sketch the phase portrait for the following system of equations using isoclines without linearising around the fixed points: & = zx _ y21 Using your phase plane, classify all of the fixed points. (4 marks)|