2021 · Q79
Consider the following for the next two (02) items that follow : A chord of a circle of radius 2.1 cm subtends an angle of 120° at the centre. (take π = 22/7 and √3 = 1.732). What is the approximate area of minor segment of the circle ?
Elementary MathematicsCircles
- A2.71 cm²
- B2.42 cm²
- C1.91 cm²
- D1.71 cm²
Explanation
Minor segment = sector − triangle = (120/360)πr² − ½r²sin120°. With r = 2.1, π = 22/7, sin120° = √3/2 ≈ 0.866: (1/3)(22/7)(4.41) − (1/2)(4.41)(0.866) = 4.62 − 1.91 = 2.71 cm². This is option (a).