float z, x;
    int a=1, b=3;
    const float e=2.71;
    cout << "Введите х=";
    cin >> x;
    cout << endl;
    if (x>=2)
        {z=sin(ax);
        cout << "z=" << z;
        }
    else
    {
        if (x<2)
            {z=pow(e,-ax)cos(bx);
            cout << "z=" << z;
            }
    }
    return 0;
}