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A Regular Polygon with 48 sides: Area, Perimeter, Interior and Exterior Angles, Inradius, Circumradius



A regular polygon with 48 sides where the length of each side is 5 units. The units may either be inches or cm or km or miles: any unit of length.

You are given a Regular Polygon with 48 sides. What are the interior angles and exterior angles? 
If the length of each side is 5 units, what is the perimeter, area, circum-radius and in-radius of the polygon?

n = 48

Perimeter of a polygon with 48 sides = (side length) x 48 = 240 units

Area of a polygon with 48 sides = (n x Sidecot (Π/n))/4 = (n x 5cot (Π/48))/4 = 4577.11 square units

Sum of the interior angles of a polygon with 48 sides = 
 (n-2) x 180 degrees =  (48-2) x 180 degrees = 8280 degrees

Interior Angle of a polygon with 48 sides = (n-2) x 180/n degrees = (48-2) x 180/48 degrees = 172.5 degrees 

Exterior angle of a polygon with 48 sides = 180 - Interior Angle = 180 - 172.5 = 7.5 degrees

Inradius = Radius of In-circle = (side length) x cot (Π/48) = 5 x cot 3 = 76.28 units

Circumradius = Radius of Circum-circle = (side length) x cosec (Π/48) = 5 x cosec 3 degrees = 76.44 units

Symmetry Group = D48  48 rotational symmetries and 48 reflection symmetries. The "D" stands for di-hedral. 




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