Mathematics for IGCSE & O level - Circle Theorems (Section 2 - No. 16)
What relationship exists between the angles marked with letters in the circles?
Angles in the same segment are always equal.
The angle between a tangent and a chord is equal to the angle in the alternate segment.
Opposite angles of a cyclic quadrilateral are supplementary.
The angle at the centre is half the angle at the circumference.
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First three options are correct, and the angle at the center is twice, not half, the angle at the circumference.