若不等式\(f\left( x \right) 0\)的解集为\(\left\{ {x\left| {1 x 2} \right.} \right\}\)

“微信扫一扫”进入题库练习及模拟考试

已知函数\(f\left( x \right) = \left( {x - 1} \right)\left( {ax + 1} \right)\)，其中\(a\in \text{R}\).

若不等式\(f\left( x \right) > 0\)的解集为\(\left\{ {x\left| {1 < x < 2} \right.} \right\}\)，求\(a\)的值；

参考答案：\( - \frac{1}{2}\)