1 . 如图,多面体
由正四面体
和正四面体
组合而成,棱长为
.
(1)证明:
;
(2)求
与平面
所成角的正弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/58c9303278abd92b7d696727c540c703.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0bf9718967af7a01c5b4866ea6f73bbb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/75bf01006f888d50f60b0735eab922c3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/38387ba1cadfd3dfc4dea4ca9f613cea.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2024/2/29/521bc74c-d84e-41fb-a726-59f5d31ab16b.png?resizew=162)
(1)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/27e2bd8134f694c7594c0a4f61b73ae3.png)
(2)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d4aca03910382accfe738520daf689c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bef5239ddbb0972700ce01daf9ee7cf.png)
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2 . 某工厂去年12月试产1060个高新电子产品,产品合格率为
.从今年1月份开始,工厂在接下来的两年中将生产这款产品.1月按去年12月的产量和产品合格率生产,以后每月的产量都在前一个月的基础上提高
,产品合格率比前一个月增加
,则今年4月份的不合格产品的数量是( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3866b3757d05ceb0d14427142fb52e9d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a8573cb8f49eb811131a5c1f5a8c6436.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/05fe56a8fa91f304581b200024d3abb4.png)
A.![]() | B.![]() | C.![]() | D.![]() |
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解题方法
3 . 已知正项等比数列
满足
,则
( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/be9cc0be87fc580372aad5fa716e2013.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/614306cc3f34bdee4d5d885b79667645.png)
A.62 | B.30或10 | C.62或![]() | D.30 |
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4 . 如图所示,平行六面体
中,
,
.
(1)用向量
表示向量
,并求
;
(2)求
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6e09725691ee7851f54c0dee86b2bf55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/17d20d9a8058985d9847ddd99046fdb0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/22a27ea00fee0b2571c6f1e8cc943a1d.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2024/2/29/ed55734c-a610-409b-8b20-2f769dfb319c.png?resizew=113)
(1)用向量
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d68873c59a21b0cd408cdf2b47d51096.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ccec46f7c4da972fef6e940158628242.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c33e3af60b6aa94f39bbd04470d2e404.png)
(2)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/388e976ab53ad76d39c74b59a09b1663.png)
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5 . 已知等差数列
的首项
,公差
,在
中每相邻两项之间都插入3个数,使它们和原数列的数一起构成一个新的等差数列
是数列
的前
项和.以下说法正确的是( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f64d5b1d831630334e494c39d0343872.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/73d774634e468a66a09297481b477cf0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f36fd6bea267ea60b09f2ac5e4f2e8f3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
A.![]() | B.![]() ![]() |
C.当![]() ![]() | D.![]() ![]() |
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6 . 已知圆
.
(1)求
的取值范围;
(2)当
取最小正整数时,若点
为直线
上的动点,过
作圆
的一条切线,切点为
,求线段
的最小值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fbc89e472c76209e2d947d7c04d19796.png)
(1)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/294f5ba74cdf695fc9a8a8e52f421328.png)
(2)当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/294f5ba74cdf695fc9a8a8e52f421328.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/20a2d3859a3980a051da34dbb60ddf1b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bd33764ff4efddfe11a98a609753715c.png)
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7 . 已知圆
,则圆心
和半径
分别为( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/aa8ec71c76d61056747152bb03077e4c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/11bc05f41215f9894e11d1df0465751a.png)
A.![]() | B.![]() |
C.![]() | D.![]() |
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解题方法
8 . 若
,则
的大小关系为( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/37bdf6c717b55e538c0aad07df12cb1d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/76f0649064a085fb74c997fb507a9b6d.png)
A.![]() | B.![]() | C.![]() | D.![]() |
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解题方法
9 . 若直线
与直线
平行,则![](https://staticzujuan.xkw.com/quesimg/Upload/formula/380bbacf854e30e2e747fc286d2b9997.png)
______ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ca60b3a4f30d07d1cf7f4ff655524ff4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/019776216e3febdc5567e9f7dce9a021.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/380bbacf854e30e2e747fc286d2b9997.png)
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10 . 双曲线
,则双曲线
的渐近线方程为( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4fb94feb15e2f43c035cff0928dae35f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
A.![]() | B.![]() | C.![]() | D.![]() |
您最近一年使用:0次