名校
解题方法
1 . 已知正三角形
,某同学从A点开始,用掷骰子的方法移动棋子.规定:①每掷一次骰子,把一枚棋子从三角形的一个顶点移动到另一个顶点.②棋子移动的方向由掷骰子(点数为
)决定,若掷出骰子的点数大于3,则按逆时针方向移动;若掷出骰子的点数不大于3,则按顺时针方向移动.设掷骰子n次时,棋子移动到
处的概率分别为
,
,
.例如:掷骰子一次时,棋子移动到
处的概率分别为
,
.当掷骰子7次时,棋子移动到A处的概率
值为___________ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bef5239ddbb0972700ce01daf9ee7cf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/31364ad692afbccf9394d9c507bb7d1a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/24e0c10fb103930eabd5fa18e8f9bb06.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8a244cf6ac956323ea14e09c5e175448.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8cb0bd2ca3d26328ec2b084b2c125568.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f73c7414b319cc405e24e3ffeba6d193.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/24e0c10fb103930eabd5fa18e8f9bb06.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/93fd65a127fa10f99b47610ccda1e70b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/71d6d9da4747ebac1de03ac6cf24067c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/81f06a99cb24d7b311fa1907a0ccb4f6.png)
您最近一年使用:0次
2023-04-05更新
|
691次组卷
|
2卷引用:广西玉林市博白县中学2022-2023学年高二下学期期中测试数学试题
2 . 设数列
的前
项和为
,且
与
的等差中项为
.
(1)证明:数列
是等比数列;
(2)设
,证明:
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/96abfe2da27a63e6affb19a0c80236d9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/47b6f30d133e86188d9e5185720bdbb7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d6ac430c4ce342d868e9399ef45ed4d4.png)
(1)证明:数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a080c94bf1ffea8d5af10f9688978fb5.png)
(2)设
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2414b9e4bf818edab0bfb752bc73aeb2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e6b6aa1778c3b6fd9d5e148da3f34f1e.png)
您最近一年使用:0次