由于x^2-x+1=(x-1/2)^2+3/4>0
故不等式就等价于ax^2-ax-x+1>0
ax^2-(a+1)x+1>0
(1)a>0:
x^2-(1+1/a)x+1/a>0
(x-1)(x-1/a)>0
(i)a>1,1/a1或x