如图,三棱柱
中,
,
,点
,
分别在
和
上,且满足
,
.
![](https://img.xkw.com/dksih/QBM/2022/5/29/2989841092280320/2992542634631168/STEM/ab798b79f6214540b426903829ea3e18.png?resizew=179)
(1)证明:
平面
;
(2)若
为
中点,求
的长.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/42d3a82b8e587ee890467835bc4e854c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f90e17995e2f71e297d94ae51c7e5b1f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1f1aa2a175b729cc5caee99e809e40b6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54a5d7d3b6b63fe5c24c3907b7a8eaa3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/24bb49fdc6b6bbb2449fdf8a0de769d3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/75a8673c4f89a0c79f454b1a1e939f19.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/caf2496aa984cd7293424dd64506f937.png)
![](https://img.xkw.com/dksih/QBM/2022/5/29/2989841092280320/2992542634631168/STEM/ab798b79f6214540b426903829ea3e18.png?resizew=179)
(1)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1eaa5e336f830a3e5cd60ff7a756f3ef.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ab3e0dba5705e1d749cfb21ebbb2ed93.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0d8772aa893a9c1d40f714cb25701701.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e2c3d2cba96f6f03520c0b3f6e4da03e.png)
21-22高二下·江苏宿迁·阶段练习 查看更多[2]
更新时间:2022-06-02 10:06:29
|
相似题推荐
解答题-证明题
|
适中
(0.65)
名校
解题方法
【推荐1】图,在正三棱柱
中,O为
与
的交点,M为
的中点,
.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/2/1/967cb39e-51f9-4598-8df3-d77f92111cbc.png?resizew=191)
(1)证明:
平面
;
(2)若G为线段FC上一动点,在平面
上是否存在一点N,使得
平面
恒成立?若存在,请找出点N位置并证明
平面
;若不存在,请说明理由.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/73a9ad711b25c36dae0c2a2cedff9954.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b470c4e195cf7a07b7a331ce4b436e03.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e26d9636ad77369535852c6e4493446a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d7f6f93171329d508d491143b9d71f7b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/393ebfea258a58906706888f0d6f2582.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/2/1/967cb39e-51f9-4598-8df3-d77f92111cbc.png?resizew=191)
(1)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fa1211fdbcc2a4a36e24b4e6c5c920bd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/99b16cff607cdc2d69afc70dc778acbb.png)
(2)若G为线段FC上一动点,在平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e9edc50f7febbc2d5d8dcdc23a3630a7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/49e6c97d975d4b04061715c41c00e1e5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b0b14cf4977ee2dac0bd5b0fca4dadc3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/49e6c97d975d4b04061715c41c00e1e5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b0b14cf4977ee2dac0bd5b0fca4dadc3.png)
您最近一年使用:0次
解答题-证明题
|
适中
(0.65)
名校
【推荐2】如图,在三棱柱
中,
平面
,点
,
分别在棱
和棱
上,且
为棱
中点.
(1)求证:![](https://staticzujuan.xkw.com/quesimg/Upload/formula/19ef601ca1f9c4c031adab4ffed297f0.png)
平面
;
(2)若
,求二面角
的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/42d3a82b8e587ee890467835bc4e854c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8a8bfe2553e852df73185d017c0a62fb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f91f0d1a4e368147e3783c9374461b3c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2777840758e70e7dbbc18cef8f3d6d2b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d88bf46ad08f9677c37eed1d0369329.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3d8379e02133be85a72747674b14f86f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/11ddc92d84d188c66b435664a7e7b5a4.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/10/20/bcd417f3-2372-40f6-9065-4f82b3115e7e.png?resizew=150)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/19ef601ca1f9c4c031adab4ffed297f0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fb31ef428bd9de9bc875b343feded3c7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0278f9809e118b80c9946d9b9ae40c83.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bffd657e48b15b9b54a55817e2c26b22.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/024d58baa25d2565912a9e6e3a06dbe2.png)
您最近一年使用:0次
解答题-证明题
|
适中
(0.65)
【推荐3】如图,在棱长为2的正方体
中,
,
,
,
分别为
,
,
,
的中点,点
为线段
上的动点,且
(
).
![](https://img.xkw.com/dksih/QBM/editorImg/2023/2/2/5bcdb284-5a76-448b-89fe-64e166ac17d9.png?resizew=154)
(1)若
为线段
的中点,求证:
平面
;
(2)是否存在
,使得二面角
的余弦值的绝对值为
?若存在,请求出
的值;若不存在,请说明理由.
![](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/a0ed1ec316bc54c37c4286c208f55667.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/895dc3dc3a6606ff487a4c4863e18509.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/73465a1f9aa03481295bf6bd3c6903ac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/394c5d2f55221975503be8aa18022480.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/11ddc92d84d188c66b435664a7e7b5a4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e0a851907ada2ac2c3c4880a6736d28a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/56f7ba05c54b3de1f4378f7c8eb58328.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d88bf46ad08f9677c37eed1d0369329.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0354c8e3cb0c61402811d41d466a4ff7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dd3ede869e508a8c8bda34a16782f863.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/2/2/5bcdb284-5a76-448b-89fe-64e166ac17d9.png?resizew=154)
(1)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d88bf46ad08f9677c37eed1d0369329.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5311bb2a8564c3ff0d683d443633f746.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ffe8a84ca3a13f82aff1a022edc66065.png)
(2)是否存在
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/df64046e91b047037f19e4032e3b6de3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cd16e4d561eac22285a01e2453f4a8f4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8c1dcde204f06aed61dd2aa5eac5a642.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/df64046e91b047037f19e4032e3b6de3.png)
您最近一年使用:0次
解答题-问答题
|
适中
(0.65)
解题方法
【推荐1】在三棱锥
中,
,
,
,M,N分别为
,
的中点,设
,
,
.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/12/19/dd85dfa3-bfbe-417a-b671-069a573df9dc.png?resizew=156)
(1)用
,
,
表示
,并求
;
(2)求
与
所成角的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4278c0911e7df78965e78cff69cac5f5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fbab39da847da8a559994b6c6004aa60.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3825ccc273ef9a672a606432d165b866.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83e44a1cc4d47b13f6c3b69544c7d026.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/828628c0876b45381c9a0edeb0fec236.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/14390e9b6b44472bdc7a131133ab39b1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/87cd14dfc0024459f9d8e594c95c5106.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e07dcf0b16163e0e0e0c0f248466ee7e.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/12/19/dd85dfa3-bfbe-417a-b671-069a573df9dc.png?resizew=156)
(1)用
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/64c5562bd4d1b54424330cb6329cd79d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b45ba716f03748c19b7ce2f99af536ab.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/73a0b19e69be46452425916a0fcb49c9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4a014dff8997c661055229de29c61cfc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8e4ea7acf140086ae816a4025d2683dc.png)
(2)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/aaf3369e0ea90e8d5cf4b6b3c45c0fd8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/279563c3c055777ce1aa369a2ef54aed.png)
您最近一年使用:0次
解答题-问答题
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适中
(0.65)
名校
【推荐2】如图:三棱柱
中,
,
是
的中点.
![](https://img.xkw.com/dksih/QBM/2023/12/29/3399611519729664/3399741726941184/STEM/4b0e1135c33b48b6b61fe94845d2d00d.png?resizew=128)
(1)求
的长;
(2)若点
是棱
所在直线上的点,设
,当
时,求实数
的值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/42d3a82b8e587ee890467835bc4e854c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8ae085a6e115d9519419db9f3ee18ac6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/598031e9c32cc829c5181e685cf8bb2b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://img.xkw.com/dksih/QBM/2023/12/29/3399611519729664/3399741726941184/STEM/4b0e1135c33b48b6b61fe94845d2d00d.png?resizew=128)
(1)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a604466a9c8d10d557b3dfc43b547065.png)
(2)若点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ab35850dbc661ded6456b70767cc6cd0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a4ba627416dad7af38eec520e2fcd70e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/793bb46a1588d171bd14e5dccd729aa4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/36a1b09c653185842513e24ebba60bb3.png)
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