如图,在
中,
,四边形
是边长为
的正方形,平面
平面
,若
,
分别是
的中点.
![](https://img.xkw.com/dksih/QBM/2018/1/18/1862923341905920/1863204283293696/STEM/5933eaf43ea84ccea205c0ee3a0342f0.png?resizew=149)
(1)求证:
平面
;
(2)求证:平面
平面
;
(3)求几何体
的体积
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0faed94a64b2dcfc6801b4fca0f16675.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6321a96e7f0768394f6932a121adc84e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e1d70676406f26d339465fe3473c0c05.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7b331bbdd68d110681fc4547748b93bb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5352d28609d1b3d09a0a29d023d1bb72.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bef5239ddbb0972700ce01daf9ee7cf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/895dc3dc3a6606ff487a4c4863e18509.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a0ed1ec316bc54c37c4286c208f55667.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/85de410d85be189dfa5aabb33410b896.png)
![](https://img.xkw.com/dksih/QBM/2018/1/18/1862923341905920/1863204283293696/STEM/5933eaf43ea84ccea205c0ee3a0342f0.png?resizew=149)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c05952cdf83c61053d809ce3f4487e39.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bef5239ddbb0972700ce01daf9ee7cf.png)
(2)求证:平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/14172212b7b34eaf967c5a72233621c6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b4eb7e9ad5486cf1c5e506b20c5469e8.png)
(3)求几何体
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4600f06bfbf134993b7d816f33d3e444.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/be54e84508decfcce6d2fcbe6c8c1a92.png)
更新时间:2018-01-18 20:01:43
|
相似题推荐
解答题-问答题
|
适中
(0.65)
【推荐1】如图,四棱锥
中,
,底面四边形
是直角梯形,
,
,且
,平面
平面
.
(1)证明:
;
![](https://img.xkw.com/dksih/QBM/editorImg/2022/9/16/f08bd392-c217-406f-bb34-ed2b3160d56b.png?resizew=149)
(2)若
,求直线
与平面
所成角的正弦值;
(3)在(2)的条件下,求三棱锥
的体积.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a21158c6a4bb5d42e75fef98bf72ca27.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ae17686725a5ecc001c809cfc35d1429.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0760712e3e2ea02b755b751e760d0c55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/080db3af81b29ed10144a1c2e2a4fb8a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dd4685bc53d11be0f30476c377d76561.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/881e92cb28c063e1c9604af43b7e9db4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fb23a04ac9df27fb987126e7ba0f6c6b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0760712e3e2ea02b755b751e760d0c55.png)
(1)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/650c6c818df102a83ce5159e3208d01a.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/9/16/f08bd392-c217-406f-bb34-ed2b3160d56b.png?resizew=149)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/65bc379448d8e65b05d099d6767c38fa.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d40b319212a7e7528b053e1c7097e966.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4e8a20c1fc8a5620db5db3a74eb01201.png)
(3)在(2)的条件下,求三棱锥
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1afa1d42c3742b2e558a1aa44cd4d032.png)
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解答题-问答题
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适中
(0.65)
名校
解题方法
【推荐2】四棱锥
,
,
,
,
底面
,
,
为
的中点.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/2/2/0df66bf9-95bd-4b5c-9d3b-41e5700327d4.png?resizew=140)
(1)证明:
;
(2)求三棱锥
的体积.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/13ff5ff92f2505a933d0213039f4c014.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/88fcb0a9670eb5925ad093f335ac3bcc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/34e0a957a55460c72673c0f2ee90dbb3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/126bb720d6f59a0de820d23c4139c1db.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/b912920e47be501b51c4a53d86e626eb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e0629ce42392a7fe9be21d25c39c3e64.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/2/2/0df66bf9-95bd-4b5c-9d3b-41e5700327d4.png?resizew=140)
(1)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/28a844f09647c16b3bc9bf1fe7f2c27b.png)
(2)求三棱锥
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/acb6f73375463f304e513ba7f4ab8058.png)
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解答题-问答题
|
适中
(0.65)
名校
【推荐1】如图,在三棱柱
中,
底面ABC,
,点M为
的中点.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/8/2/69ffb319-a4ed-44ba-9b70-248ed1e38765.png?resizew=133)
(1)证明:
平面
;
(2)棱AC上是否存在点N,使二面角
的大小为
,若存在,求
的值;若不存在,请说明理由.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/42d3a82b8e587ee890467835bc4e854c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5845ccc0d735dc14c92a8926d9b1def6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4eea99ab0ec843cb28f353b9b0bc27f7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/56f7ba05c54b3de1f4378f7c8eb58328.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/8/2/69ffb319-a4ed-44ba-9b70-248ed1e38765.png?resizew=133)
(1)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/89006cac018a9875f65ed7bd429c61bf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/de9078475c350c04bd97666d808dd55a.png)
(2)棱AC上是否存在点N,使二面角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b7165738abe803afb6ace7ed0c555508.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/af9955b5aebb73cd84447e8541f901ac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6b3b161fc5c52c8243866e88f3790a22.png)
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解答题-证明题
|
适中
(0.65)
【推荐2】如图,在正方体
,
为
的中点,
交平面
交于点
.
(1)求证:
为
的中点;
(2)点
是棱
上一点,二面角
的余弦值能否等于
?若能,求
的值;若不能,说明理由.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6e09725691ee7851f54c0dee86b2bf55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/394c5d2f55221975503be8aa18022480.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/56f7ba05c54b3de1f4378f7c8eb58328.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/10fc7991ea17d54ff5f4445ac5699463.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a0ed1ec316bc54c37c4286c208f55667.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2024/4/9/6f4c4a3d-04c6-41e3-94e2-9ca9f036add8.png?resizew=167)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a0ed1ec316bc54c37c4286c208f55667.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/56f7ba05c54b3de1f4378f7c8eb58328.png)
(2)点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/11ddc92d84d188c66b435664a7e7b5a4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e3209af8b0dd3ddd5ca3f74563bbcda5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3fe2c533dbc23a34518f72f3cb14f330.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b27940ef045f9701269a2740a0d09fc8.png)
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解答题-证明题
|
适中
(0.65)
【推荐1】如图所示,在四棱锥E-ABCD中,平面ABCD⊥平面AEB,且四边形ABCD为矩形.∠BAE=90°,AE=4,AD=2,F,G,H分别为BE,AE,AD的中点.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/1/6/ad28322d-50a6-4fbb-862e-4742ceb2feb7.png?resizew=174)
(Ⅰ)求证:CD∥平面FGH;
(Ⅱ)求证:平面FGH⊥平面ADE;
(Ⅲ)在线段DE求一点P,使得AP⊥FH,并求出AP的值.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/1/6/ad28322d-50a6-4fbb-862e-4742ceb2feb7.png?resizew=174)
(Ⅰ)求证:CD∥平面FGH;
(Ⅱ)求证:平面FGH⊥平面ADE;
(Ⅲ)在线段DE求一点P,使得AP⊥FH,并求出AP的值.
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【推荐2】如图,在五面体ABCDEF中,FA⊥平面ABCD,
,若![](https://staticzujuan.xkw.com/quesimg/Upload/formula/74aa71480d770188fc29821999d97e9f.png)
.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/4/16/5ec13246-d7c7-4df6-b1b0-05135ee07da4.png?resizew=182)
(1)求五面体ABCDEF的体积;
(2)若M为EC的中点,求证:平面
平面AMD.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/abd9f608b8362c2a375dd9926a110152.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/74aa71480d770188fc29821999d97e9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ee11b995ab36bd4a1149fc1a30acfc99.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/4/16/5ec13246-d7c7-4df6-b1b0-05135ee07da4.png?resizew=182)
(1)求五面体ABCDEF的体积;
(2)若M为EC的中点,求证:平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/79c1acdd27cebb11e0266464b03b3afb.png)
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