Let ABCDEF be a regular hexagon. Let P be the circle inscribed in △BDF. Find the ratio of the area of circle P to the area of rectangle ABDE.
Solution
Solution:
12π3 Let the side length of the hexagon be s. The length of BD is s3, so the area of rectangle ABDE is s23. Equilateral triangle BDF has side length s3. The inradius of an equilateral triangle is 3/6 times the length of its side, and so has length 2s. Thus, the area of circle P is 4πs2, so the ratio is s23πs2/4=12π3.
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Source: MathNet,
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