(i) Differentiate \(y\) to obtain \(3\sin^2 t \cos t - 3\cos^2 t \sin t\).

Use \(\frac{dy}{dx} = \frac{dy/dt}{dx/dt}\).

Obtain given result \(-3\sin t \cos t\).

(ii) Identify parameter at origin as \(t = \frac{3}{4}\pi\).

Use \(t = \frac{3}{4}\pi\) to obtain \(\frac{3}{2}\).

(iii) Rewrite equation as equation in one trig variable, e.g. \(\sin 2t = -\frac{2}{3}\).

Find at least one value of \(t\) from equation of form \(\sin 2t = k\).

Obtain \(t = 1.9\).

Obtain \(t = 2.8\) and no others.