关于x的不等式ax^2+(a-1)x+a-1
问题描述：
关于x的不等式ax^2+(a-1)x+a-1
答
ax^2 + (a-1)x + a-1x^2 + (a-1)x/a x^2 + (a-1)x/a + [(a-1)/(2a)]^2[(x + (a-1)/(2a)]^2 因为 [(x + (a-1)/(2a)]^2 ≥ 0
所以 (1-a)/a + [(a-1)/(2a)]^2 ≤ 0
(1-a)/a + (a-1)^2/(4a^2) ≤ 0
两边同乘以
4a(1-a) + (a-1)^2 ≤ 0
4a - 4a^2 + a^2 -2a +1 ≤ 0
2a - 3a^2 +1 ≤ 0
3a^2 -2a -1 ≥ 0
再往下你自己应该会解了?