Komplekse tal i c++

Kode 

   
std::complex<double> c(0,1);
std::cout << pow(c,2);

Kode 

#include <iostream>
#include <complex>

int main()
{
   std::complex<double> a(1, 2);
   std::complex<double> b(3, 4);

   std::cout << a << " * " << b << " = " << a * b << std::endl;
}

Kode 

   std::complex<double> a(-1, 0);
   std::cout << "SQRT(-1): " << sqrt(a) << std::endl;

Kode 

#include <iostream>
#include <math.h> 
#include <complex>

using namespace std;
int main ()
{
float a;

float b;

float c;

float result;

float result1;

float result2;

char ae=-111; //æ

char oe=-101; //ø

cout << "Goddag\n"; 
cout << "Indtast din a v"<<ae<<"rdi: "; 

cin >> a;
cout << "Din a v"<<ae<<"di er sat til at v"<<ae<<"re "<<a<<" \nIndtast nu din b v"<<ae<<"rdi: ";

cin >> b;

cout << "Din b v"<<ae<<"di er sat til at v"<<ae<<"re "<<b<<" \nIndtast nu din c v"<<ae<<"rdi: ";
cin >> c;


cout << "Din c v"<<ae<<"rdi er sat til at v"<<ae<<"re "<<c<<", \n og din andengradsligning er derfor "<<a<<"x^2+"<<b<<"x+"<<c<<".\n\n";

result = (b * b) - 4 * a * c;

cout << "Diskriminanten for din andengradsligning er derfor "<<result<<".\n";

result1 = (-sqrt(result) - b) / 2 * a;
result2 = (sqrt(result) - b) / 2 * a;
cout << "Dine l"<<oe<<"sninger er "<<result1<<" og "<<result2<<"";

cin.ignore();

cin.get();
return 0;

}