1 . 已知三棱锥P-ABC的平面展开图中,四边形ABCD为边长等于
的正方形,△ABE和△BCF均为正三角形,在三棱锥P-ABC中:
![](https://img.xkw.com/dksih/QBM/editorImg/2022/10/28/4ba5efea-4e0a-45a8-854b-fb8c44425128.png?resizew=345)
(1)证明:平面PAC⊥平面ABC;
(2)若点M为棱PA上一点且
,求二面角P-BC-M的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/95bacae35b6e16a0a33c2bdc6bc07df7.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/10/28/4ba5efea-4e0a-45a8-854b-fb8c44425128.png?resizew=345)
(1)证明:平面PAC⊥平面ABC;
(2)若点M为棱PA上一点且
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dcd9780b6f5b877fc09ddd7f0b001dc8.png)
您最近一年使用:0次
2012·湖北·二模
名校
2 . 已知向量
,
,设函数
.
(1)若
,
,求
的值;
(2)在△
中,角
,
,
的对边分别是
且满足
求
的取值范围.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dcfb57f603089caca97c4b3f7b1dc426.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c467247e56151abc1ff5c3baf518cd51.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/16cddfeda152e262474f1a4f656f30e9.png)
(1)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/778662c16848db470c6537705b8a839c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fc76ed86d0b368e8587c913fe57c1623.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/81dea63b8ce3e51adf66cf7b9982a248.png)
(2)在△
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bef5239ddbb0972700ce01daf9ee7cf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/76f0649064a085fb74c997fb507a9b6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac45dff9eec277ea2d4e2f383dc510f0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9de0f6d2b676fb885e43df4db0ed66d9.png)
您最近一年使用:0次
2020-01-01更新
|
605次组卷
|
10卷引用:2019年全国高中数学联赛甘肃省预赛
2019年全国高中数学联赛甘肃省预赛(已下线)2012届湖北省八校高三第二次联考理科数学试卷(已下线)2012届江西省高安中学高三第三次模拟考试理科数学试卷(已下线)2012届江西省高安中学高三第三次模拟考试文科数学试卷(已下线)2014届重庆市第八中学高三第六次月考理科数学试卷2017届湖南长沙长郡中学高三上周测十二数学(理)试卷2018年上海市青浦区高三4月质量调研(二模)数学试题(已下线)上海市华东师范大学第二附属中学2022届高三下学期6月练习数学试题上海市高桥中学2022届高三上学期12月月考数学试题云南省德宏州民族中学2015届高三上学期第二次月考数学(文)试题
3 . 已知数列
中,
,且![](https://staticzujuan.xkw.com/quesimg/Upload/formula/73ac8bd72ba5b540cdc31c074981763c.png)
(1)求数列
的通项公式;
(2)证明:对一切
,有
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fe49088cdaf4bfb36acb0cb5bc4104c7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/73ac8bd72ba5b540cdc31c074981763c.png)
(1)求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
(2)证明:对一切
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/29d5ec9ad92f37e64eccce922ab1b14e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f07076f74b7748a93669dcdd0b3696d.png)
您最近一年使用:0次
2018-12-25更新
|
647次组卷
|
4卷引用:2019年全国高中数学联赛甘肃省预赛
2008高三·甘肃·竞赛
4 . 斜率为1的直线交
轴于点
,与以
轴为对称轴、开口向右且过点
的抛物线交于点
,点
与抛物线顶点的距离为
.求抛物线的方程.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/81dea63b8ce3e51adf66cf7b9982a248.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/81dea63b8ce3e51adf66cf7b9982a248.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/455ba3d3e46977fcbe5b71f8bb9df4be.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d0c74f41a07c10e293c38109bf5b22d7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d599cb4a589f90b0205f24c2e1fa021e.png)
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2010高三·甘肃·竞赛
5 . 设
是一些互不相同的四元数组
的集合,其中,
或
.已知
的元素个数不超过15,且满足:若
、
,则
、
,其中,
,
.求集合
元素个数的最大值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cf231f8f86fb922df4ca0c87f044cec3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f93191a3ce77ad660d167f906cb3242c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ca64ef9e0c3dd14e99d113dbbe973ace.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d9bb9cc49d5fefbc0ae8a5a6f808d52c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cf231f8f86fb922df4ca0c87f044cec3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f93191a3ce77ad660d167f906cb3242c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/657bd53f165c7247b4f01b5ddd93b478.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6c15fa4d238d578e6ee5812bd5ad322c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4c58108683a07648483ec7cde489bbf5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2f31742b2bbb5eea5e58dcfa5145e6ba.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d7aaa967b11d295d9ba9d9c91702e3a0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cf231f8f86fb922df4ca0c87f044cec3.png)
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2010高三·甘肃·竞赛
6 . 对任意的正整数
,证明:
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f7371819a1790b665acbeaa2bd491b0f.png)
您最近一年使用:0次
2010高三·甘肃·竞赛
7 . 设
,
,…,
是1,2,…,
的一个排列.求证:
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e72adb45c60c2f63b46e65ff787302bf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3e88093a749c0d46e0ee931ecfaff925.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/96abfe2da27a63e6affb19a0c80236d9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8715a3f984d2627afd7c40c61347b7cb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/576a1192c5b580bed1b5fcbad8ce18cb.png)
您最近一年使用:0次
2010高三·甘肃·竞赛
解题方法
8 . 已知
,
.求
的值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/46ef9cb1a7f6a03e6fe654f632b21a22.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/763c9c979c19460aea9ccf74418dae10.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/671f24578769e3ad9d710f858625ffee.png)
您最近一年使用:0次
9 . 设
、
、
成等差数列,
;
、
、
成等比数列,
.若
、
、
是正整数且成等比数列,求
的最大值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e72adb45c60c2f63b46e65ff787302bf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3e88093a749c0d46e0ee931ecfaff925.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6c1ccc6c74b8754e9bcbb3f39a11b6f1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a84917c4f840f34385c1621a26e45fb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b715e7842b95f654f16056a7c7f2abe9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/13423c094861baf4b759b7f3d8c3c226.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/57483e04fd1840c87ac5325157149877.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a43afec39f6e70e87cc291788cea5679.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ea74a5cf39bd1149aed1ce6c8ba0c895.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9b183d4f49ce99fcf3dc335fc41b6c5d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5f04dc034b37dcd72288ddcbe9e9544b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6c1ccc6c74b8754e9bcbb3f39a11b6f1.png)
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