public static void main(String[] args){ double a,b,c,x1,x2; Scanner sc = new Scanner(System.in); System.out.println( "请输入a" ); a = sc.nextDouble(); System.out.println( "请输入b" ); b = sc.nextDouble(); System.out.println( "请输入c" ); c = sc.nextDouble(); x1 =(-b+Math.sqrt(b*b-4*a*c))/(2* a); x2 =(-b-Math.sqrt(b*b-4*a*c))/(2* a); System.out.println( "x1="+x1+"x2="+ x2);

。 这里的"^"表示乘方。