Question

sin3°thetha=cos2°thetha prove that thetha=18°​

Answer 1

Answer:

sin 3theta= cos theta

sin 3theta = sin (90-2theta)

On comparing,

3 theta=90°-2theta

3 theta+2theta=90°

5 theta=90°

theta=18°

Answer 2

use sin theta=cos(90- theta)