名校
解题方法
1 . 数列
对任意
且
,均存在正整数
,满足
,
,
.
(1)求
可能值;
(2)若
,
成立,求数列
的通项公式.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/48f093c61867ee4ce75f951d46b9b123.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0704f453b2de48d36911f7db496bbf82.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fa2c9d76530a39e790d4e60206878a9b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/520dafa0c218cc4273e39ff68819ead6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b065334d8f60c49f4bd3d9f1373fe4cd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2693734765399876e9e93cdb110231c4.png)
(1)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/daf464629fa321a6ff7401ab79f07083.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/98da601bb35509b0126adfd7068386ed.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4510bacdfd0023b9146eb500f8ca26ab.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
您最近一年使用:0次
名校
解题方法
2 . 如图1,与三角形的三边都相切的圆叫做三角形的内切圆.设O是△ABC的内切圆圆心,
内是△ABC的内切圆半径,设
是△ABC的面积,
是△ABC的周长,由等面积法,可以得到
内
.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/29/e3da696e-d797-4178-ab24-f0087aafa165.jpg?resizew=358)
(1)与三棱锥的四个面都相切的球叫做三棱锥的内切球.设三棱锥的体积是
,表面积是
,请用类比推理思想,写出三棱锥的内切球的半径公式
内(只写结论即可,不必写推理过程);
(2)如图2,在三棱锥
中,
,
,
两两垂直,且
,求三棱锥
的内切球半径和外接球的半径之比.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/11bc05f41215f9894e11d1df0465751a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b5cbff84327e964f912a54032e76ccc9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a8c261982132e55c19fd25ad50c6f3b5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/11bc05f41215f9894e11d1df0465751a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e4fcc80a88cb1dc8fd4184f5b8225814.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/29/e3da696e-d797-4178-ab24-f0087aafa165.jpg?resizew=358)
(1)与三棱锥的四个面都相切的球叫做三棱锥的内切球.设三棱锥的体积是
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/be54e84508decfcce6d2fcbe6c8c1a92.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cf231f8f86fb922df4ca0c87f044cec3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4aa0df7f1e45f9de29e802c7f19a4f64.png)
(2)如图2,在三棱锥
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63397cda22cb1fad59cf966dfb588643.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bd33764ff4efddfe11a98a609753715c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d2be49c37e30a3ced0364c3e74d8c687.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/48f3c9abbd78e9a6840ee5f30381daac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/50094bfee564d9c1b03088ac2ece28c3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63397cda22cb1fad59cf966dfb588643.png)
您最近一年使用:0次
2021-12-29更新
|
442次组卷
|
3卷引用:四川省南充市白塔中学2022-2023学年高三上学期入学考试数学(理)试题
名校
3 . (1)已知
,
,
,用反证法证明:
中至少有一个不小于
;
(2)用数学归纳法证明:
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/24a57996290794e082b21d8f1dfc322a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cab560cdc1f2fff8483e64235774d2aa.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/695a08f451a58854ed4453aee7de8c87.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/76f0649064a085fb74c997fb507a9b6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bdaa19de263700a15fcf213d64a8cd57.png)
(2)用数学归纳法证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c431e455f71a9a0ab6649846a4f117c4.png)
您最近一年使用:0次
2020-03-15更新
|
244次组卷
|
2卷引用:四川省成都市树德中学2019-2020学年高二下学期开学考试数学试题