4 A curve is defined by the parametric equations $$x = 4 \cos ^ { 2 } t , \quad y = \sqrt { 3 } \sin 2 t$$ for values of \(t\) such that \(0 < t < \frac { 1 } { 2 } \pi\).
Find the equation of the normal to the curve at the point for which \(t = \frac { 1 } { 6 } \pi\). Give your answer in the form \(\mathrm { ax } + \mathrm { by } + \mathrm { c } = 0\) where \(a , b\) and \(c\) are integers.