解题方法
1 . 如图,在多面体
中,
平面
,四边形
是正方形,
.
与平面
所成角的余弦值;
(2)证明:
平面
;
(3)求三棱锥
的体积.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d9bf53e97203aa720fe3a09b9bf534af.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ccd4fd4b7a4d6b8ca0c5827c055a9ce7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fe240da6d51d3efea02af13e73b87ab1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9a9fd76d8997e3b2db7d9cb9b72d0f80.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/85c4bdfb0db1e31e8459df1d15f9ab55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f2e30e6cd7e777ccd3edb50a9bd3163c.png)
(2)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/db807b09cc550f476b3f8fa0c6a14425.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c09afc70f448545336304333d5b5658b.png)
(3)求三棱锥
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c4ca19321c6776be24e4be5033b60ed7.png)
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2 . 已知空间中两条不同的直线
和两个不同的平面
,则下列说法正确的是( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/280860dd039e1305a5ccc455f63e8223.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c4e288596fa3811dd2c17bded60e82e7.png)
A.若![]() ![]() |
B.若![]() ![]() |
C.若![]() ![]() |
D.若![]() ![]() |
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3 . 正方体
中,
为
的中点,则直线
与直线
所成角为( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6e09725691ee7851f54c0dee86b2bf55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8cfbc0b5a8fbde804bd8425a4b76d207.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9fd17a66a2af938c89e46f22e4d893b1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d7f6f93171329d508d491143b9d71f7b.png)
A.![]() | B.![]() | C.![]() | D.![]() |
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4 . 如图是一个正四棱台
,已知正四棱台的上、下底面的边长分别为
和
,体积为
,则此正四棱台的高为__________
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6e09725691ee7851f54c0dee86b2bf55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/61128ab996360a038e6e64d82fcba004.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6f8c4c029e552954bd493b49aeab82d5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8a965ef4b938192a74937fcacb7a907f.png)
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5 . “巍然古塔耸西城,炮弹横遭削不平”,诗句描述的就是位于江苏省无锡市江阴市西横街的兴国寺塔,兴国寺塔已成为江阴人民不屈不挠精神的象征,某数学兴趣小组成员为测量该塔的高度,在塔底
的同一水平面上的
两点处进行测量,如图.已知在A处测得塔顶
的仰角为60°,在
处测得塔顶
的仰角为45°,
米,
,则该塔的高度
( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/01c74a907dda6bb7d9d56d009d9df253.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e7cfd87c08fc5ee8723f4f263a94b576.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a3434c5450f52f38e9d2409f164fe2f3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/88bedc4627a1777defeb106ef597d0db.png)
A.![]() | B.![]() |
C.![]() | D.60米 |
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6 . 已知
是同一平面内的三个向量,
.
(1)若
为单位向量,且
,求
的坐标;
(2)若
,且
与
垂直,求
与![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b45ba716f03748c19b7ce2f99af536ab.png)
夹角
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2e12e95f703ad30ab9a3d38376830989.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b981b38133d5d65060dd8ff4d65a66be.png)
(1)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/73a0b19e69be46452425916a0fcb49c9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5dd43c3c9a578b91fe832c4c2477103c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/73a0b19e69be46452425916a0fcb49c9.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e7a09bede8bcb942fc0a17b8300cfa47.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/437dc907211c5934f938d869f6b19e93.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c67a5673958e175b00200a75e645c73c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/64c5562bd4d1b54424330cb6329cd79d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b45ba716f03748c19b7ce2f99af536ab.png)
![](https://img.xkw.com/dksih/QBM/2024/4/25/3483210128482304/3523740179324928/STEM/c75277594e5341938380bceb0f145b6a.png?resizew=14)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c24095e409b025db711f14be783a406c.png)
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7 . 八卦是中国文化的基本哲学概念,图1是八卦模型图,其平面图形为图2所示的正八边形
,其中
给出下列结论正确的是( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d17d4a6cf11cda87b3dfafaecdec683f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/473f0b41bb8eb316ea6bc719b33d4a48.png)
A.![]() ![]() ![]() | B.![]() |
C.![]() | D.![]() |
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解题方法
8 . 若圆锥的轴截面是斜边为4的等腰直角三角形,则该圆锥的体积为( )
A.![]() | B.![]() | C.![]() | D.![]() |
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解题方法
9 . 记
的内角
的对边分别为
,且
.
(1)求
;
(2)若
,
的面积为
,求
的周长
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/24e0c10fb103930eabd5fa18e8f9bb06.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/76f0649064a085fb74c997fb507a9b6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9b11d83cc4abd3886788064b177a46c4.png)
(1)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3f5b763032c085a1e60822d8dc1b3605.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/38387ba1cadfd3dfc4dea4ca9f613cea.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
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解题方法
10 . 已知平行四边形
中,
,
,
.若点
满足
,点
为
中点,则![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f33bd925dbc5bda5c705f6a3400c66c.png)
__________
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/00dc923e1b4f6a795bfd70cd698dfdd3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7872abd162e356132bb371fc581d818c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/51c3a1f1a37e69b2dc06bf0affd58f22.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a06d84898e2aed657ca46546f870c304.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54a5d7d3b6b63fe5c24c3907b7a8eaa3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f33bd925dbc5bda5c705f6a3400c66c.png)
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