如图,在长方体
中.
![](https://img.xkw.com/dksih/QBM/2020/7/24/2512860608864256/2512977270177792/STEM/871c0a7b-ce7a-4bdb-b0ea-0d41cc5b0661.png)
(1)求证:
平面
;
(2)若
,求直线
与平面
所成角的正弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6e09725691ee7851f54c0dee86b2bf55.png)
![](https://img.xkw.com/dksih/QBM/2020/7/24/2512860608864256/2512977270177792/STEM/871c0a7b-ce7a-4bdb-b0ea-0d41cc5b0661.png)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fcc3f049152c43dd29b12d0a60aa79f3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9539f8fb13345b449274b67bbda995db.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3f0b24d3b14c326b2baa2d2c5e8db871.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/10d8eb4a9f462ca0c1d49c3fe91e720d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9539f8fb13345b449274b67bbda995db.png)
更新时间:2020-07-24 20:48:15
|
相似题推荐
解答题-证明题
|
适中
(0.65)
名校
【推荐1】在四棱锥
中,底面ABCD是菱形,
底面ABCD,
,
,点M为PB的中点.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/6/20/8cf38e64-c1a7-41ca-93eb-c9bc1e799f78.png?resizew=195)
(1)求证:
平面MAC;
(2)在棱CD上是否存在一点F,使得
,若存在,求PF与平面PAD所成角的正弦值;若不存在,请说明理由.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0585b6c0f156eecf9662b9846d4eb693.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ccd4fd4b7a4d6b8ca0c5827c055a9ce7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c3b10835116b9b777a666b438c907b49.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9eee296a7d9fba487f1485c61580196f.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/6/20/8cf38e64-c1a7-41ca-93eb-c9bc1e799f78.png?resizew=195)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/36222db36e348661eb5f616820e4e60f.png)
(2)在棱CD上是否存在一点F,使得
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cf6de7703e18a31c8081be4d2d31bb01.png)
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解题方法
【推荐2】如图,多面体
中,四边形
是矩形,
面
,
交
于点
.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/13/adc4bc56-c502-456a-bbdd-b25e9fe33e1d.png?resizew=212)
(1)证明:
面
;
(2)证明:
面
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9165d9bfbb0f0d19eb482c2a4c1b29b7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6c89136b8bc834b20c88387c477d3ae5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4a64d84cb02fcfca2a369a2977e336b6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/41158d8e437a803a716f95039fa41bfe.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d40b319212a7e7528b053e1c7097e966.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/13/adc4bc56-c502-456a-bbdd-b25e9fe33e1d.png?resizew=212)
(1)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5f25093ed95c672bec55b8a3b4a293db.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2977ae4bfa32de8c6f0fb136205c4fe7.png)
(2)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9f4c3f9dd5d0343597a7f58a1989b537.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2977ae4bfa32de8c6f0fb136205c4fe7.png)
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解答题-证明题
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解题方法
【推荐3】如图,在三棱台
中,
,.若点
为
的中点,点
为
靠近点
的四等分点.
![](https://img.xkw.com/dksih/QBM/2020/5/10/2459899048656896/2462413519577088/STEM/77c3dc44be4145b1b8618c023013c847.png?resizew=265)
(1)求证:
平面
;
(2)若三棱台
的体积为
,求三棱锥
的体积.
注:台体体积公式:
,或在
分别为台体上下底面积,
为台体的高.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/42d3a82b8e587ee890467835bc4e854c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0b4c1b05c1c1024dd6836dbea9b9db3b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d88bf46ad08f9677c37eed1d0369329.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54a5d7d3b6b63fe5c24c3907b7a8eaa3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://img.xkw.com/dksih/QBM/2020/5/10/2459899048656896/2462413519577088/STEM/77c3dc44be4145b1b8618c023013c847.png?resizew=265)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7592c4f01c8e06c7ee90df5b9413a9f5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ab3e0dba5705e1d749cfb21ebbb2ed93.png)
(2)若三棱台
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/42d3a82b8e587ee890467835bc4e854c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c2a0722573c30df895c2c288fae80c10.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fa7d8ebbebd9a58d2cce6e662a34b23c.png)
注:台体体积公式:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9a8a389dac52166517c02c4129cf8e4e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8ab93d9afb14d07b81567d47207c4be0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3eabd5f3a86afe49dcd70571e2b96cfd.png)
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解答题-问答题
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适中
(0.65)
【推荐1】如图,已知多面体ABCD-
,AA1,BB1,CC1,DD1均垂直于平面ABCD,AD//BC,AB=BC=CD=AA1=CC1=2,BB1=1,AD=DD1=4.
![](https://img.xkw.com/dksih/QBM/2021/6/6/2736984060076032/2738362151772160/STEM/eaf9107b-26dc-4674-90f9-c993911030fe.png?resizew=206)
(1)证明∶
⊥平面
;
(2)求直线BC1与平面AB1C1所成的角的正弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/632f2bf1cd0435041fa04b01901d1c8c.png)
![](https://img.xkw.com/dksih/QBM/2021/6/6/2736984060076032/2738362151772160/STEM/eaf9107b-26dc-4674-90f9-c993911030fe.png?resizew=206)
(1)证明∶
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f1f229274a6e17977cc047814212589.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/82b724168afaee2ecddf97257180be18.png)
(2)求直线BC1与平面AB1C1所成的角的正弦值.
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解答题-证明题
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适中
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【推荐2】如图,三棱柱ABC-AlB1C1中,AC=BC,AB=AA1,∠BAA1=60°.
![](https://img.xkw.com/dksih/QBM/2020/10/26/2579551082840064/2581389846970368/STEM/689df258-ec98-493d-a938-b81d59a88d83.png?resizew=314)
(1)求证:A1C⊥B1A1;
(2)若平面ABC⊥平面ABB1A1,且AB=BC,求直线CB1与平面A1BC所成角的正弦值.
![](https://img.xkw.com/dksih/QBM/2020/10/26/2579551082840064/2581389846970368/STEM/689df258-ec98-493d-a938-b81d59a88d83.png?resizew=314)
(1)求证:A1C⊥B1A1;
(2)若平面ABC⊥平面ABB1A1,且AB=BC,求直线CB1与平面A1BC所成角的正弦值.
您最近一年使用:0次
解答题-证明题
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适中
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名校
【推荐3】如图,在四棱锥
中,底面
是矩形,
平面
,且M是
的中点,
,
.
(1)求证:
平面
;
(2)求
与平面
所成角的余弦值.
![](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/ccd4fd4b7a4d6b8ca0c5827c055a9ce7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e0629ce42392a7fe9be21d25c39c3e64.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8c2753753faf2cb9a0003aa8e3945159.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fcd0ced286a0fbc7e4862f8147264277.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/11/15/948c2216-389d-414c-85b0-3e0374a16b81.png?resizew=162)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7d0edb1508fc95765f3bb316bcb5252d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/80f747eb5b2d21c9de962cbfd4ec4bb7.png)
(2)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d50703c46b6153945d718b198f03b4b5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a2730b513bd3359c3dfe6567e04f5ef9.png)
您最近一年使用:0次