Need help solving matlab error

% code %1st part t = 0:0 1: 5; x = 52*t 9*t^2; y = 125-5* t^2; plot(t, x, t, y) title('y vs x'); %2nd part t = 0:0.1:5 vx = [-9 52 0] vy = [-5 0 125]; vx 1 = polyder(vx) vy = polyder(vy) v = squareroot (vx1.^2 + vy1.^2) plot(v, t) titlet('v vs t')