1 . 已知
,不等式
恒成立.
(1)求
的值
;
(2)若方程
有且仅有一个实数解,求ab的值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a788b2d8cce011455e549a59ebc5c92b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6ce9dc4b97804d00d682fed1b04a7eb0.png)
(1)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/34a8eb19e30aa486abf1b0dfb3d3bd6c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/294f5ba74cdf695fc9a8a8e52f421328.png)
(2)若方程
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5c5cbe4c9cd2831801f4a564641b8d90.png)
您最近一年使用:0次
2 . 已知函数![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c84496f87abcf6d9c51c25391d6f55d7.png)
,
,给出下列四个结论:
①函数
在区间
上单调递减;
②函数
的最大值是
;
③若关于
的方程
有且只有一个实数解,则
的最小值为
;
④若对于任意实数a,b,不等式
都成立,则
的取值范围是
.
其中所有正确结论的序号是_______ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c84496f87abcf6d9c51c25391d6f55d7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dcd9218a657b17654c5d757a6f7dee9a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8ba56d22e9f7803b5545f91e1e0c2a62.png)
①函数
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/09f86f37ec8e15846bd731ab4fcdbacd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ccfdd3d02b54e997cbec983d80f6bafd.png)
②函数
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4669810732b633b60dbeaf0bf57204f6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f89eef3148f2d4d09379767b4af69132.png)
③若关于
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/81dea63b8ce3e51adf66cf7b9982a248.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7c0008d46dc238d710a1efe7e2c17237.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/294f5ba74cdf695fc9a8a8e52f421328.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f89eef3148f2d4d09379767b4af69132.png)
④若对于任意实数a,b,不等式
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a0dec45d8c4760288f233275bdfcae96.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/294f5ba74cdf695fc9a8a8e52f421328.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/19094cbb9d60021934728b1d3daf8a9b.png)
其中所有正确结论的序号是
您最近一年使用:0次