Important: The number of diagonals in a polygon that can be drawn from any vertex in a polygon is three less than the number of sides. To find the total number of diagonals in a polygon, multiply the number of diagonals per vertex (n - 3) by the number of vertices, n, and divide by 2.
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The number of diagonals in a hexagon is => [(6 - 3) * 6]/2 = 9
If the side of a hexagon is 1 unit, then 3 diagonals have the lengths of 2 units, and 6 diagonals have the lengths of √3.
So, the product of all 9 diagonals is => 8 ( 81√3 )