Mathematics for IGCSE & O level - Circle Theorems (Section 1 - No. 33)
If a chord of a circle subtends an angle of 120 degrees at the center, what is the angle subtended by the same chord at a point on the major arc?
30°
60°
90°
120°
คำอธิบาย
The angle at the circumference is half the angle at the center.