Question

express cos75 + cot75 in terms of angles between 0 to 30.

Answer 1

$$\begin{gathered} \cos 75°+\cot 75° \\ =\cos \left(90°-15°\right)+\cot \left(90°-15°\right) \\ =\sin 15°+\tan 15°\{\mathrm{since},\cos \left(90°-\mathrm{\theta }\right)=\mathrm{sin\theta }\mathrm{and}\cot \left(90°-\mathrm{\theta }\right)=\mathrm{tan\theta }\} \end{gathered}$$