1 . 在数列
中,若
,则称
为“等方差数列”.下列是对“等方差数列”的判断:
①数列
是等方差数列;
②若
是等方差数列,则
是等差数列;
③若
是等方差数列,则
(
,k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.
其中正确的命题序号为________ .(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/6bb7f9567c40424df0e76cf07be4b1f3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
①数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/df31060266f95483c3b391b8e35d9192.png)
②若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/362832fa3d3c13c1eafd565349d66dce.png)
③若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/39a561552fc52b697f1a7f1c81c2f637.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/31e36bff57bcfa86432b340e25e51d42.png)
④若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
其中正确的命题序号为
您最近一年使用:0次
2004高三·河南·竞赛
名校
解题方法
2 . 某宇宙飞船的运行轨道是以地球中心F为焦点的椭圆,测得近地点A距离地面m(km),远地点B距离地面n(km),地球半径为R(km),关于这个椭圆有以下四种说法:
①焦距长为n-m;②短轴长为
;③离心率
;④若以AB方向为x轴正方向,F为坐标原点,则与F对应的准线方程为
,其中正确的序号为______ .
①焦距长为n-m;②短轴长为
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e8fd953c16000841146a7bcc4fde6946.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/654a0fd2b7d5bd743e36725c5a1edba0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7d41ce8e2dd35159ec77eb0fe68c9085.png)
您最近一年使用:0次
2022-12-22更新
|
236次组卷
|
5卷引用:2004年全国高中数学联赛河南省预赛试题
(已下线)2004年全国高中数学联赛河南省预赛试题安徽省滁州市定远县育才学校2021-2022学年高二普通班上学期期末文科数学试题安徽省滁州市定远县育才学校2021-2022学年高二(普通班)上学期期末考试数学(文)试题福建省泉州第五中学2022-2023学年高二下学期第二次临考数学仿真模拟试题(B)(已下线)期末真题必刷易错60题(34个考点专练)-【满分全攻略】2023-2024学年高二数学同步讲义全优学案(人教A版2019选择性必修第一册)
3 . 将4个相同的红球和4个相同的蓝球排成一排,从左到右每个球依次对应序号为1,2,…,8,若同颜色的球之间不加区分,则4个红球对应序号之和小于4个蓝球对应序号之和的排列方法种数为
A.31 | B.27 | C.54 | D.62 |
您最近一年使用:0次
2016-12-03更新
|
673次组卷
|
3卷引用:数学奥林匹克高中训练题_73
4 . 若
,
,则下列判断①
,②
,③存在
,使
,④存在
,使
;也存在
,使
中,正确的序号为______ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6eec7d75a66a4407631f75320bb8b15.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bcd08434ba3d0a0d162a7ffaf593998a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4118df6374966db0ef68716dfa9a13e2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d5e67796c688457d65ce0af594ca476b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c24095e409b025db711f14be783a406c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/44ecf39ce99b3fad69512154416deb39.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c24095e409b025db711f14be783a406c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4118df6374966db0ef68716dfa9a13e2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c24095e409b025db711f14be783a406c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d5e67796c688457d65ce0af594ca476b.png)
您最近一年使用:0次
5 . 已知
.给出下列结论:①
;②
;③存在
,使
;④存在
,使
.其中,正确结论的序号为______ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/025d8f85233cdc40a41d36d55f70eb4c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1c73a98c1b3504e09bfbe0db849b0d24.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a71baf6217604517fd98fa97d0f55b43.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f7dbb416ec1ff1984a724a4f48bf692.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c36825543013336c9df727bc51ff62c6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f7dbb416ec1ff1984a724a4f48bf692.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/92755ed40510a358dcb77392749fd792.png)
您最近一年使用:0次
6 . 给出下列命题:
①
;
②若
,则
;
③若
,则
;
④若
、
,
,则
.
其中,正确命题的序号为______ .
①
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e8ebc553c60f28b5c67843f2db951ff7.png)
②若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6d42c49064a9c51c13cacb822e327336.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0a1f1d909f18e5cf13c48762f2a31080.png)
③若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6eec7d75a66a4407631f75320bb8b15.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/17eec784c002a80ba88c7f2e1b895b52.png)
④若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0a6936d370d6a238a608ca56f87198de.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/67ca5fd57c2c2fcc3c7a574fdd1467d9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/20c11f6c800b8e0410674a0c6d307d26.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d4bc9bd873f21d1470ad0810259e084e.png)
其中,正确命题的序号为
您最近一年使用:0次
名校
7 . 给出下列两个命题:(1)设
,
,
都是复数.如果
,则
;(2)设
,
,
都是复数,如果
,则
.那么,下述说法正确的是
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0a6936d370d6a238a608ca56f87198de.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2c94bb12cee76221e13f9ef955b0aab1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/071a7e733d466949ac935b4b8ee8d183.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/95563a79e3b68c597ae1e5167516ff88.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fd96385362fd2bc879f32ae00e9a6fd3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0a6936d370d6a238a608ca56f87198de.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2c94bb12cee76221e13f9ef955b0aab1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/071a7e733d466949ac935b4b8ee8d183.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fd96385362fd2bc879f32ae00e9a6fd3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/95563a79e3b68c597ae1e5167516ff88.png)
A.命题(1)正确,命题(2)也正确 | B.命题(1)正确,命题(2)错误 |
C.命题(1)错误,命题(2)也错误 | D.命题(1)错误,命题(2)正确 |
您最近一年使用:0次