2.设x1x_{1}x1,x2x_{2}x2是关于xxx的方程x2+(a−1)x+a+2=0x^{2}+(a-1)x+a+2=0x2+(a−1)x+a+2=0的根.若−1<x1<1-1<x_{1}<1−1<x1<1,1<x2<21<x_{2}<21<x2<2,则实数aaa的取值范围是((( )))