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[Community Question] Geometry: Two circles and Four circles inside a regular hexagoan

One of our user asked:

https://uva.onlinejudge.org/index.php?option=com_onlinejudge&Itemid=8&page=show_problem&problem=1228 enter image description here can't find the 2nd and 4th case... 1st case is six equlatiral triangle and the area is sqrt(3)/2*side = 1/2*side*height so height =sqrt(3)/2*side

and 3rd case is 2*height =sqrt(3)/2*side so height = (sqrt(3)/2*side)/2

here height is the radius.


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