答案：B2x2-4x+1=0根据根与系数之间的关系得，x1+x2=2，x1x2=1/2x1/x2+x2/x1=(x12+x22)/x1x2 =[(x1+x2)2-2x1x2]/x1x2 =6 x4-16=(x2)2-42 =(x2+4)(x2-4) =(x2+4)(x+2)(x-2)
