What are the formulas for angles inside or on a circle for their arcs

The video tutorial reviews three types of angles related to circles: central angles, inscribed angles, and angles formed by chords or secants. Central angles have their vertex at the circle's center, and their measure equals the arc's measure. Inscribed angles have their vertex on the circle, and their measure is half the arc's measure. Angles formed by chords or secants inside the circle are calculated as half the sum of the measures of the arcs they intercept.

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