Question

if tan 42=0.9,then find the value of cot 492

Answer 1

Dear Student,

$$\begin{gathered} \tan 42°=0.9 \\ cot492°=cot(360+132)°=cot\left(132\right)°=cot(90+42)° \\ asweknowcot(\frac{\mathrm{\pi }}{2}+x)=-\tan x \\ cot(90+42)°=-\tan 42°=-0.9 \\ cot492°=-0.9 \end{gathered}$$

Regards,