Soln

 = cos 1470° (\(\therefore\) (-\(\theta\)) = cos\(\theta\))

 = cos(16 x 90° + 30°)

 = cos 30°

 = \(\frac{\sqrt(3)}{2}\)

Soln

 = -tan 570° (tan(-\(\theta\) = -tan \(\theta\))

 = -tan(7×90° - 60°)

 = {-cot60°}

 = cot 60° = \(\frac{1}{\sqrt(3)}\)