推 jacky7987 :1. (x^2-3)(x^2-2) Q(sqrt(2),sqrt(3)) 是splitting 05/27 22:39
→ jacky7987 :2. If f(x)=x^3+qx+r and let D^2=-4q^3-27r^2 05/27 22:40
→ jacky7987 :if D^2 is a square in Q, then Gal=A_3 05/27 22:40
→ jacky7987 :if not, then Gal=S_3 05/27 22:40
推 jacky7987 :To transfer to the form just Let X=x-1/3 05/27 22:43