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Polygon in Annulus
A polygon of side length two is shown with a circle circumscribing its vertices. A second circle is shown with the sides of the polygon tangential to the circle. The challenge is to calculate the area of the resulting annulus in terms of π. The result is always π, independent of the number of sides of the polygon.
The formal derivation of the result relies on calculating the area of each circle, factorising the result, and then substituting the length of the side into the result.
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Polygon in Annulus: presentation 419.45 KB
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Polygon in Annulus: support file 175.71 KB
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