Given the linear ODE: x(3) + 3x + 4x + 2x = u(t) (a) Convert this third order ODE into first-order form = f(z, u) where z is a 3 x 1 vector (b) With u = 0 and the initial conditions x(0) = 1, x(0) = -1, x(0) = 1 determine the value of the vector (0). Given below is a system of two nonlinear differential equations. x + 2xye* + xy = 0 +x + 2y sin(x) = 0. Convert the nonlinear system to first-order form.