1 . 在数列
中,若
为常数
,则
为“等方差数列”,下列是对“等方差数列”的判断;
①
是等方差数列,则
是等差数列;
②
是等方差数列;
③ 若
是等方差数列,则![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bed8c521ba833022d7f57a4d44b2824f.png)
为常数
也是等方差数列;
④ 若
既是等方差数列,又是等差数列,则该数列为常数列.
其中正确命题序号为__________ .(将所有正确的命题序号填在横线上)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1ca1c0c66577dd728e61895ebc96b3ae.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/04582116cd765fcc5a52f44279ad6c94.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
①
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c806dc9bf2cad0cb20220d23bd252a2f.png)
②
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4ef891fc99921b6093392c1e3c5347d1.png)
③ 若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bed8c521ba833022d7f57a4d44b2824f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d3b6a244eab64b41c3f98222feb04855.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/04582116cd765fcc5a52f44279ad6c94.png)
④ 若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
其中正确命题序号为
您最近一年使用:0次
名校
解题方法
2 . 已知正四棱柱
的底面边长为2,侧棱
为上底面
上的动点,给出下列四个结论:
①若PD=3,则满足条件的P点有且只有一个;
②若
,则点P的轨迹是一段圆弧;
③若PD∥平面
,则DP长的最小值为2;
④若PD∥平面
,且
,则平面BDP截正四棱柱
的外接球所得图形的面积为
.
其中所有正确结论的序号为_____ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6e09725691ee7851f54c0dee86b2bf55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b48eab2e9070bf8d094193ea52f1129a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/632f2bf1cd0435041fa04b01901d1c8c.png)
①若PD=3,则满足条件的P点有且只有一个;
②若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/71826134c3080aa75becc655a9089855.png)
③若PD∥平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/13cfdc6224181d44e63aab43ddaf07ef.png)
④若PD∥平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/13cfdc6224181d44e63aab43ddaf07ef.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/71826134c3080aa75becc655a9089855.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6e09725691ee7851f54c0dee86b2bf55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7b2dfd7c4a190b8dbbc56f2fcc2b2ce0.png)
其中所有正确结论的序号为
您最近一年使用:0次
2019-01-21更新
|
823次组卷
|
4卷引用:广东省东莞市光明中学2021届高三下学期期初考试数学试题
解题方法
3 . 如图是函数
的导函数图象,给出下面四个判断:①
在区间
上是增函数;②
是
的极小值点;③
在区间
上是增函数,在区间
上是减函数;④
是
的极小值点.所有正确判断的序号是( )
![](https://img.xkw.com/dksih/QBM/editorImg/2022/6/22/c5eedf63-4269-45eb-8066-620e5ce8dacb.png?resizew=207)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/51c530f4b7491b95acb8ce3eef9aa09d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4fe7d5809da02c15a43a0e9a898b9086.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f2b2e67cd10ebbced3d964ab0dc5c298.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/99c6875d552e9fff3c7d655f3a59b166.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4fe7d5809da02c15a43a0e9a898b9086.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4fe7d5809da02c15a43a0e9a898b9086.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/23c33b69adc112831fa115b5dffdb616.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0de71d25c72850e383a4c841eed0db99.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/707ea658f3a9359f5740d5aab48f7948.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4fe7d5809da02c15a43a0e9a898b9086.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/6/22/c5eedf63-4269-45eb-8066-620e5ce8dacb.png?resizew=207)
A.①② | B.②③ | C.③④ | D.①②③④ |
您最近一年使用:0次
4 . 下列叙述随机事件的频率与概率的关系中,说法正确的是( )
A.频率就是概率 |
B.频率是客观存在的,与试验次数无关 |
C.随着试验次数的增多,频率越来越接近概率 |
D.概率是随机的,在试验前不能确定 |
您最近一年使用:0次