[TEX]2/ Tim\ tat\ ca\ cac\ gia\ tri\ m\ de\ phuong\ trinh\ sau\ co\ dung\ 3\ nghiem\ :[/TEX]
[TEX]x^4+12x^3+4(9-m^2)x^2-8mx-4=0[/TEX]
[TEX]HD\ :\ nhom\ thanh\ tich\ hai\ tam\ thuc\ bac\ 2[/TEX]
[TEX]5/\ Cho\ x,y\ la\ cac\ so\ thuc\ thoa\ man\ :[/TEX]
[TEX]x-2\sqrt{x+1}=2\sqrt{y-1}+1-y[/TEX]
[TEX]Tim\ GTLN,GTNN\ cua\ bieu\ thuc\ \ P=x+y[/TEX]
[TEX]HD\ :\ Luong\ giac\ hoa[/TEX]