---

#include <iostream>
#include <cmath>
using namespace std;
int main() {
    double a, z2;
    cout <<"wedite a"<<endl;
    cin>>a;
    z2= 2 * sqrt(2) * cos(a) * sin (M_PI/4 + 2 * a);
    cout << z2;
    return 0;
}
  





#include <iostream>
#include <cmath>
using namespace std;
int main() {
    double a, z3;
    cout <<"wedite a"<<endl;
    cin>>a;
    z3= (1 - 2*pow(sin(a), 2)) / (1 + sin(2*a));
    cout << z3;
    return 0;
}







#include <iostream>
#include <cmath>
using namespace std;
int main() {
    double a, z4;
    cout <<"wedite a"<<endl;
    cin>>a;
    z4= pow((1 + a + a*a) / (2*a + a*a) + 2 - (1 - a + a*a) / (2*a - a*a), 2) * ( 5 -2 *a*a);
    cout << z4;
    return 0;
}







#include <iostream>
#include <cmath>
using namespace std;
int main() {
    double m,n, z1;
    cout <<"wedite m,n"<<endl;
    cin>>m>>n;
    z1 = ((m - 1) * sqrt(m) - (n - 1) * sqrt(n)) / (sqrt(m*m*m*n) + n*m + m*m - m);
    cout << z1;
    return 0;
}