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° = \(\frac{1}{\sqrt(3)}\)

Questions and Answers on Signs of Trigonometric Ratios

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° = \(\frac{1}{\sqrt(3)}\)