23-24高二下·全国·课前预习
解题方法
1 . 性质
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dae141920c1e115a152bba17f79172b6.png)
______________ ,
(
为常数)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dae141920c1e115a152bba17f79172b6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fd6e1dfc7d8cd132a9d91d1632621419.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/071a7e733d466949ac935b4b8ee8d183.png)
您最近一年使用:0次
2 . 方差的定义:如果
的平均数为
,那么方差可用求和符号表示为![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ab4f3fe82a2da9fee7695cb90dc4946e.png)
________ =_______ .
方差的性质:如果a,b为常数,那么
的方差为________ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1fe1c31a81f198c443e71b83ca662939.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c85481cd7e94130ef3aa05b4a39e79cd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ab4f3fe82a2da9fee7695cb90dc4946e.png)
方差的性质:如果a,b为常数,那么
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/de7ad5db90cf74cf46360e462c04a17f.png)
您最近一年使用:0次