If two tangents inclined at an angle of 120° are drawn to a circle of radius 6 cm, then what is the length (in cm) of each tangent?
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Correct answer: B
Explanation
The correct answer is Option 2 i.e. .

We know that tangents drawn from an external point are equally inclined to the line joining that point to the center
⇒ ∠APO = ∠BPO = ∠APB/2 = 120/2 = 60°
Now In ΔΟΑΡ
⇒ ∠OAP = 90° (Tangent is perpendicular to the radius at the point of contact)
Now in the right ΔOAP
⇒ ∠OPA = 60°
⇒ tan 60° = OA/AP
From the trigonometric table tan 60° = √3
⇒ √3 = 6/AP
⇒ AP = 6/√3 = 2√3
Also, tangents drawn from an external point are equal in length
⇒ AP = PB = 2√3