1 real coefficient equation is written on the paper;

(2)b & gt； A 2-4b when δ= 0, if δ

△ 1=p^2-4q=p^2-4b/p，

If p; 0, q<0. Let x 2+px+q = 0 be m.

Then m < 0<n, m+n =-p >; 0，| m | & ltn，

If m2-4n >；; =0, let x 2+MX+n = 0 be R.

r^2-4s<； =n^2-4√n，

For r 2-4 s > =0, you need √ n > =4，n & gt= 16;

And so on,