Question: Find the derivatives

(a) \(R=3{{\sin }^{-1}}\left( 4-{{t}^{2}} \right)\)

(b) \(y={{\tan }^{-1}}\left( 1-x \right)\)

(c) \(\theta =\frac{{{\tan }^{-1}}\left( 2r \right)}{\pi r}\)