Q. The angles of a triangle are in the ratio 2 : 3 : 7 and the radius of the circumscribed circle is 10 cm. The length of the smallest side is
WBJEEWBJEE 2019
Solution:
In the figure $\Delta$ABC is the respective triangle, O is the circumcentre. $∠AOB = 2∠ACB = 2 × 30^{\circ} = 60^{\circ} \Rightarrow ∠OAB = ∠OBA = 60^{\circ} \Rightarrow \Delta OAB$ is equilateral $\Rightarrow OA = AB = OB = 10\, cm.$
