# Shortest Path between Two Points in the Unit Disk Reflecting off the Circumference

Shortest Path between Two Points in the Unit Disk Reflecting off the Circumference

Given two points within the unit disk labeled (in green) and (in red), what is the shortest path between the two points that reflects off the unit circle? You can drag the two points.

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The central angle between the two points is . The angle from the axis to is . The shortest path that touches the unit circle is at angle .

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