Given a n-sided polygon with side length a. The task is to find the area of the cicumcircle of the polygon.
Input: n = 10, a = 3 Output: 1.99737 Input: n = 5, a = 6 Output: 3.02487
Approach: A regular n-gon divides the circle into n pieces, so the central angle of the triangle is a full circle divided by n: 360 deg/n.
Applying the law of cosines for the three side lengths of the triangle, we get
c2 = a2 + b2 – 2ab cos C
or, a2 = r2 + r2 – 2rr cos (360/n)
or, a2 = 2r2 – 2r2 cos (360/n)
or, c2 = r2 (2 – 2 cos (360/n))
Below is the implementation of the above approach:
- Program to find the Perimeter of a Regular Polygon
- Program to find the Interior and Exterior Angle of a Regular Polygon
- Apothem of a n-sided regular polygon
- Regular polygon using only 1s in a binary numbered circle
- Area of a n-sided regular polygon with given Radius
- Length of Diagonal of a n-sided regular polygon
- Area of a n-sided regular polygon with given side length
- Side of a regular n-sided polygon circumscribed in a circle
- Program to calculate area of Circumcircle of an Equilateral Triangle
- Find number of diagonals in n sided convex polygon
- Area of Circumcircle of a Right Angled Triangle
- Area of the circumcircle of any triangles with sides given
- Check if it is possible to create a polygon with a given angle
- Area of a polygon with given n ordered vertices
- Minimum Cost Polygon Triangulation
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