$\begin{array}{1 1}(a)\;\left\{\begin{array}{1 1}-cosec\theta-\cot\theta&if\;0<\theta>\pi\\-cosec\theta-\cot\theta&if\;\pi<\theta<2\pi\end{array}\right.\\(b)\;\left\{\begin{array}{1 1}cosec\theta+\cot\theta&if\;0<\theta>\pi\\-cosec\theta+\cot\theta&if\;\pi<\theta<2\pi\end{array}\right.\\(c)\;\left\{\begin{array}{1 1}cosec\theta+\cot\theta&if\;0<\theta>\pi\\-cosec\theta-\cot\theta&if\;\pi<\theta<2\pi\end{array}\right.\\(d)\;\left\{\begin{array}{1 1}cosec\theta+\cot\theta&if\;0<\theta>\pi\\cosec\theta-\cot\theta&if\;\pi<\theta<2\pi\end{array}\right.\end{array}$