# Circumcircle of a regular polygon Calculator

## Calculates the radius and area of the circumcircle of a regular polygon.

number of sides n
 n＝3,4,5,6....
side length a

circumcircle area Sc
polygon area Sp
area ratio Sc/Sp
 $\normal Circumcircle\ of\ regular\ polygons\\\hspace{20} n:\ number\ of\ sides\\(1)\ circumradius:\hspace{50} r={\large\frac{a}{2sin{\large\frac{\pi}{n}}}}\\(2)\ circumcircle\ area:\hspace{10} S_c=\pi r^2\\(3)\ polygon\ area:\hspace{45} S_p={\large\frac{na^2}{4tan{\large\frac{\pi}{n}}}}\\$

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