1 . 如图所示,测量河对岸的塔高
时,可以选取与塔底
在同一水平面内的两个测量基点
与
,现测得
,
,
,在点
测得塔顶
的仰角为
,则塔高
为( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.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/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3d40978fbe52316daaaa6bdbb403fea0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a626567510a9d322489719fc57b744cd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ec3701b5f24bd2384bd60a7175151469.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/270800ba975e87235e8802a631e5f3a2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
A.![]() | B.![]() | C.![]() | D.![]() |
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2 . 如图所示,在四棱锥
中,
平面
,
,
,
为棱
上一点,
.
平面
;
(2)求二面角
的大小;
(3)求点
到平面
的距离.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/faeb97acf19bd3b2c6c77c2814df4d2f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/10c83f8945042b9c8fb2fbdac9308d62.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5f79863ffcfa63117ca6741b20a48e69.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2ed755c6ed8bff50bfb0599556f312c5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8a6e2867f32d3f1c3cd36cd3a11a8580.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7511d9fee222da35d0849088b215169c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15dbd6b14bd68b220859e06da3c8c4ac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8f571a1aac46c6d0cf440c0ec2846bf9.png)
(2)求二面角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/216498bbff79fe1246ad79825314617d.png)
(3)求点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8f571a1aac46c6d0cf440c0ec2846bf9.png)
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3 . 已知向量
满足
,且
,则向量
在向量
上的投影向量的坐标为______ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b8e8b95a61af300412fc65f846089028.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/338136e7ff6fe98a98c0d2142d8f48f8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/65cdd07ae1b1770d628b165db17f6a00.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7a2f4b1178f68bd147d1a2a6acd04435.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c94075193c11fe43f2396cff5a485054.png)
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4 . 已知
,
是平面内的一组基底,
,
,
,若
,
,
三点共线,则实数
的值为( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0411792b587ddd3e04440392f011c224.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b95d660852c5226ff65a21cfb36b8b39.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b762bd33ee43da74ab19450074105468.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/65cac341927963722f7fd1180aa8085f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ff40563daf96329ae2084126410a2c59.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/f0a532e15e232cb4b99a8d4d07c89575.png)
A.9 | B.13 | C.15 | D.18 |
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5 . 如图,在三棱锥
中,
平面
分别为棱PC,PB的中点.
平面
;
(2)若
,求二面角
的大小.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63397cda22cb1fad59cf966dfb588643.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ccd4fd4b7a4d6b8ca0c5827c055a9ce7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/517f89f30121be4d53d6aee05fccf044.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6d077f6da8b2c00b152d4679aa2ed7f7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b9a32bd7a1b78b5a0ec562c4025aea8c.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/587df01a98f499a9f361aafd8c3dac39.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5617a404c5a3356753136e5a6b6d51e5.png)
您最近一年使用:0次
6 . 在正四棱台
中,
,且该四棱台的体积为
,则下列说法正确的是( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6e09725691ee7851f54c0dee86b2bf55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d134433600df75f2a5d0f35deb2cac90.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7054c60c3472ee4dc7b5ea5a8d6b1b6a.png)
A.![]() |
B.该四棱台的表面积为32 |
C.直线![]() ![]() ![]() |
D.直线![]() ![]() ![]() |
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7 . 如图,在正四棱柱
中,
是棱
的中点,则直线
与BE所成角的余弦值为( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6e09725691ee7851f54c0dee86b2bf55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3abd1ed7099a0530abd382847af3bfbd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/22adbc0da438220f9cace11b629d799b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83c09eec4e14a861af83d7828797d176.png)
A.![]() | B.![]() | C.![]() | D.![]() |
您最近一年使用:0次
解题方法
8 . 如图,在直三棱柱
中,侧面ABCD的面积为
为直角,
,则三棱柱
的外接球的半径取最小值时,四棱锥
的体积为___________ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/19a01abf5ae85221309ecf031f2cd872.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/277d3553963af4243617d1dbe47100e7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/35f8fc3b7d7e1bc8241dc9b87daa79ba.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/19a01abf5ae85221309ecf031f2cd872.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/80c753cb1eb73fd8d136d00462970797.png)
您最近一年使用:0次
9 . 如图,在四棱锥
中,四边形
是梯形,
,
,
是等边三角形,
,点
是棱
的中点.
与平面
的交线为
,求证:
;
(2)求证:平面
平面
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0585b6c0f156eecf9662b9846d4eb693.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ae1e04eeb4de72e5750dae77bcb6f88a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1134c8e3440abb6cd385af2c169037fe.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/55a675310c8ba418e5a59beb7317e21e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/123bf0d9dc2e5237d63a09402da78dee.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/895dc3dc3a6606ff487a4c4863e18509.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bd33764ff4efddfe11a98a609753715c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e7b7c83470489253394bd288d7c920df.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/852aabd89edffc1b94344ff3f1f31ccd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f85fca60a11e1af2bf50138d0e3fe62.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/72ee6c7e0dfe134561f818cb51eebe09.png)
(2)求证:平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/35c9529795ba241d68e1c4ce912b4334.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1e582d73b96ba649378379c3074d506d.png)
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