//My Code
#include <iostream>
#include <stdio.h>
#include <cmath>
using namespace std;

int main()
{

    double y;
    double x = 21;


   y = 30 * sqrt(x * (1/(tan(sqrt(3*x) - 2.1))));

  printf ("The value is: n=> %f", y );


}

y = 30 * sqrt(x * (1/(tan((sqrt(3*x) - 2.1)*M_PI/180))));

printf( "sqrt(3*x) = %lfn", sqrt(3*x));
printf( "sqrt(3*x) - 2.1 = %lfn", sqrt(3*x) - 2.1);
printf( "tan(sqrt(3*x) - 2.1) = %lfn", tan(sqrt(3*x) - 2.1));

std::complex<double> two_i = std::sqrt(std::complex<double>(-4));