Let C be a circle with center O and AB be a chord of C such that the length of AB is equal to the radius of C. Let D be any point on major arc of AB. Find ∠AOB and ∠ADB, respectively.
Show answer & explanation
Correct answer: B
Explanation
The correct answer is option 2 i.e. 60°; 30°.
The angle subtended by a chord equal to the radius in a circle = 60°
AB = radius of C
So, ∠AOB = 60°
The angle subtended by the same chord at the circumference on the major arc is half of the angle subtended at the center.
So, ∠ADB = 1/2 × ∠AOB = 1/2 × 60° = 30°
Therefore, the measure of ∠AOB is 60° and ∠ADB is 30°.