假设方程形式为安心x^2+bx+c=0 两根分别为x1+y1i,x2+y2i 假设其共轭,则y1=-y2,y1+y2=0,x1=x2 b=-(x1+y1i+x2+y2i)=-(x1+x2)为实数 c=(x1+y1i)(x2+y2i)=x1x2+y1x2+y2x1+x1-y1y2=x1x2-y1y2为实数 则原方程为实系数方程,...