若A是不等边△ABC中最小的内角,且cosA=(a+1)/(a-1),则实数a的范围
0＜A＜60°
1/2＜cosA＜1
1/2＜(a+1)/(a-1)＜1
-1/2＜2/(a-1)＜0
a＜-3