← 2.2 Angle Properties of a Circle
The angle in a semicircle
Mathematics · Grade 11 · about 40 minutes
A diameter subtends 90 degrees at every point on the remaining circumference, and a right angle at the circumference means the opposite side is a diameter.
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Other lessons in this sub-strand
- Arc, chord and segment
- The angle an arc subtends
- The centre angle is twice
- The angle on the other arc
- Angles in the same segment
- Both segments of one chord
- The angle in a semicircle
- Equal radii, equal base angles
- Opposite angles of a cyclic quadrilateral
- The exterior angle
- Choose the circle theorem
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