Given here is an equilateral triangle with side length a, the task is to find the area of the circle inscribed in that equilateral triangle.
Examples:
Input : a = 4 Output : 4.1887902047863905 Input : a = 10 Output : 26.1799387799
Approach:
Area of equilateral triangle =
Semi perimeter of equilateral triangle = (a + a + a) / 2Radius of inscribed circle r = Area of equilateral triangle / Semi perimeter of equilateral triangle
=
=Area of circle = PI*(r*r) =
Below is the implementation of above approach:
// C++ program to find the area // of circle which is inscribed // in equilateral triangle # include<bits/stdc++.h> # define PI 3.14 using namespace std;
// Function return the area of circle // inscribed in equilateral triangle float circle_inscribed( int a)
{ return PI * (a * a) / 12;
} // Driver code int main()
{ int a = 4;
cout << circle_inscribed(a);
return 0;
} // This code is contributed // by Mahadev99 
// Java program to find the area // of circle which is inscribed // in equilateral triangle import java.io.*;
class GFG
{ static double PI = 3.14 ;
// Function return the area of circle // inscribed in equilateral triangle static double circle_inscribed( int a)
{ return PI * (a * a) / 12 ;
} // Driver code public static void main (String[] args)
{ int a = 4 ;
System.out.println(circle_inscribed(a));
} } // This code is contributed by anuj_67 
# Python3 program to find the area of circle # which is inscribed in equilateral triangle # import math library for pi value from math import pi
# Function return the area of circle # inscribed in equilateral triangle def circle_inscribed(a):
return pi * (a * a) / 12
# Driver code a = 4
print (circle_inscribed(a))

// C# program to find the area // of circle which is inscribed // in equilateral triangle using System;
class GFG
{ static double PI = 3.14;
// Function return the area of circle // inscribed in equilateral triangle static double circle_inscribed( int a)
{ return PI * (a * a) / 12;
} // Driver code public static void Main ()
{ int a = 4;
Console.WriteLine( circle_inscribed(a));
} } // This code is contributed // by inder_verma 
<?php // PHP program to find the area // of circle which is inscribed // in equilateral triangle // Function return the area of circle // inscribed in equilateral triangle function circle_inscribed( $a )
{ return 3.14 * ( $a * $a ) / 12;
} // Driver code $a = 4;
echo circle_inscribed( $a );
// This code is contributed // by Akanksha Rai(Abby_akku) 
Output:
4.1887902047863905
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