Arc (geometry)

In Euclidean geometry, a circular arc is a closed segment of a differentiable curve in the two-dimensional plane; for example, an arc is a segment of a circle. If the arc segment occupies a great circle (or great ellipse), it is considered a great-arc segment. The length of an arc of a circle with radius and subtending an angle (measured in radians) with the circle center—i.e., the central angle—equals . This is because Substituting in the circumference
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