如图所示,斜三棱柱
中,点
为棱
(不包括端点)上的点.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/10/24/3673b98c-9bc8-4d31-95ea-1c2be221f048.png?resizew=142)
(1)当
等于何值时,
平面
;
(2)设多面体
的体积为
,三棱柱
的体积为
,求
;
(3)若
,
,求异面直线
与
所成角的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/36cf3bff56a7f4ab6c0008e90823025d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8ac99c0358497d72001cc575f1ade329.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6b10b969819d397711310c8dbb399ebc.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/10/24/3673b98c-9bc8-4d31-95ea-1c2be221f048.png?resizew=142)
(1)当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5763b58c5b81fce6257c9792c5ef6b47.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c76388ad7f8db6bb0f37efa9700ed26a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/87eeb5402a32ccaaa0be4116e98fb00f.png)
(2)设多面体
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4f71ab444dbe3c7151181031d77be8ba.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/81f4784453d5db30fbb7df3ffa85be30.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/36cf3bff56a7f4ab6c0008e90823025d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cea87fc8705bde72f090cc253f89b0e4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a21e57b4383c59f2e78bfcec0770fc1c.png)
(3)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/322dea27776098da737428d2f7519cd8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e5ab3ca990935ac5a5545398846f6084.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dcca943ee165b1a3ff7e0cc5f463754b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15f73038249a611568193c0bcc286fd7.png)
更新时间:2022-10-21 23:21:55
|
相似题推荐
解答题-问答题
|
适中
(0.65)
名校
【推荐1】如图,三棱柱
的体积为
,侧面
是矩形,
,
,且已知二面角
是钝角.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/5/1/8a7de914-4a15-49ee-acb0-28a35de0b6e0.png?resizew=151)
(1)求
的长度;
(2)求二面角
的大小.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/42d3a82b8e587ee890467835bc4e854c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/860884c0017c8bceb5b0edff796c144f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2d9a8181f7a7fe7f3fac872ce9534f15.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/45224f7eac9d0cef64bf28d93e7721a4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/59bd979c95390db4949aafd26634e21f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9f77f400a3cf0acb19d4e4c7da2b80a7.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/5/1/8a7de914-4a15-49ee-acb0-28a35de0b6e0.png?resizew=151)
(1)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e26d9636ad77369535852c6e4493446a.png)
(2)求二面角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/058fff86f341ccaa93c75cc9f3015632.png)
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适中
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解题方法
【推荐2】如图甲,在平面四边形
中,已知
,
,
,
,现将四边形
沿
折起,使平面
平面
(如图乙),设点
、
分别为棱
、
的中点.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/20/9073037a-1da7-43b1-b029-56af5699e2fa.png?resizew=265)
(1)求证:
平面
;
(2)设
,求三棱锥
的体积.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2c7d2df86ee897fffd62a719d889d791.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f149e83812e72efd7dd3dfc78d0134ae.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e19f7ec7d20c2fdb5dbefa13e039a88c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3f5fc4ad65b723b6a8da4c8dac154e6e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d40b319212a7e7528b053e1c7097e966.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fcf6dc837ae85207789b94d109c5c2eb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b4739afd7311501e948aa4e1e5c1cb17.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/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/20/9073037a-1da7-43b1-b029-56af5699e2fa.png?resizew=265)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/689c065652544780be8b33ae92cbb6d7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bef5239ddbb0972700ce01daf9ee7cf.png)
(2)设
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/037b342a682cbd4241855a243da3c016.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/eab5b318479646033908bd5fd02ddd50.png)
您最近一年使用:0次
解答题-证明题
|
适中
(0.65)
【推荐1】如图,平面
平面
,
,
,点E,F分别在线段AB,CD上,且
.求证:
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/87a60be170a52db82cf37b30db0cde26.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5b5858ee1ce52b251816757257a11c29.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4b45bd54b36db9a944692861b93dfb49.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/56496b1ebf06fec74a531a4de3c0cd84.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0c1427dca0e261319dbd9890442122db.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4841d8f5473207f6c65cafc2c64d9d65.png)
![](https://img.xkw.com/dksih/QBM/2020/1/30/2388354048933888/2389111773585408/STEM/62770aaa5bf74c04a114121377a41da8.png?resizew=209)
您最近一年使用:0次
解答题-问答题
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适中
(0.65)
解题方法
【推荐2】如图,已知正四棱台
的侧棱与底面所成的角为
,O为下底面
的中心,
.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/7/5/2296ba12-dde3-4b95-b0dd-620aad55b2c0.png?resizew=285)
(1)证明:
平面
;
(2)求正四棱台
的体积.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6e09725691ee7851f54c0dee86b2bf55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/be6a6301878fed2a01413020b27310a5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d134433600df75f2a5d0f35deb2cac90.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/7/5/2296ba12-dde3-4b95-b0dd-620aad55b2c0.png?resizew=285)
(1)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7de4723157b880c06d8c3d379149316b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/11c3590fe4de811edc0723205a081334.png)
(2)求正四棱台
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6e09725691ee7851f54c0dee86b2bf55.png)
您最近一年使用:0次
解答题-证明题
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适中
(0.65)
【推荐3】如图,在三棱台
中,
平面
,
,
,
分别为
,
的中点
.![](https://img.xkw.com/dksih/QBM/editorImg/2022/9/6/05b0716e-21a7-4b1f-8dbe-3266420fc207.png?resizew=240)
(1)求证:
平面
;
(2)若
且
,求二面角
的大小.
![](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/7bef5239ddbb0972700ce01daf9ee7cf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/255791e63a0cf4f5e156319fae423769.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/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/9/6/05b0716e-21a7-4b1f-8dbe-3266420fc207.png?resizew=240)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1496afecd92a619fbe5e9b736f06f4e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/eae80f09dae8acbe1e5e27bd5c4d8164.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/080db3af81b29ed10144a1c2e2a4fb8a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3570a95f68349fcd9417fcda62e78e7e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/49b0e6a4fae0cf7bf0e6bbd925318d3e.png)
您最近一年使用:0次
解答题-证明题
|
适中
(0.65)
名校
解题方法
【推荐1】如图,在直三棱柱(侧棱垂直于底面的三棱柱)
中,
,
,棱
,
,
分别为
,
的中点.请用空间向量知识解答下列问题:
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/8/3ff99999-bbd8-4ccf-bd27-95d52627e890.png?resizew=154)
(1)求
;
(2)求证:
平面
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/42d3a82b8e587ee890467835bc4e854c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ca38004c7744a7567bef30f0674fe60f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1a3cc9cccfb4c260dac05f4ed57e8c10.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/92535536bd3c2761724fd058427f95a8.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/11ddc92d84d188c66b435664a7e7b5a4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2777840758e70e7dbbc18cef8f3d6d2b.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/8/3ff99999-bbd8-4ccf-bd27-95d52627e890.png?resizew=154)
(1)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e0ed85453508f2cc01318c6a81764a20.png)
(2)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3d6da9f598fecf6fcf41cd65b45cbe08.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/eae80f09dae8acbe1e5e27bd5c4d8164.png)
您最近一年使用:0次
解答题-问答题
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适中
(0.65)
【推荐2】直三棱柱
中,![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fe1e521443db04a96187e9ce6cbb19f5.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/6/c15ce7f1-b96b-4141-987e-10ab5f49336b.png?resizew=139)
(1)求异面直线
与
所成角的大小;
(2)求直线
与平面
所成角的大小;
(3)在线段
上是否存在点
,使得
?若存在,求出
的值;若不存在,说明理由.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/42d3a82b8e587ee890467835bc4e854c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fe1e521443db04a96187e9ce6cbb19f5.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/6/c15ce7f1-b96b-4141-987e-10ab5f49336b.png?resizew=139)
(1)求异面直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e26d9636ad77369535852c6e4493446a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d7f6f93171329d508d491143b9d71f7b.png)
(2)求直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/56f7ba05c54b3de1f4378f7c8eb58328.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9539f8fb13345b449274b67bbda995db.png)
(3)在线段
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0d8772aa893a9c1d40f714cb25701701.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c84a436704964dc76f16c2c23665ab3c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c04c68f1ef1e37534b5bbc7a1f592ef7.png)
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适中
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【推荐3】如图,在梯形
中,
,
,现将
沿
翻折成直二面角
.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/3/6/b45ce535-d349-4989-9607-e7523d5a3050.png?resizew=388)
(1)证明:
;
(2)若
,二面角
余弦值为
,求异面直线
与
所成角的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fcd8e727e4efc22b49649f71ae9c9d84.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/555e29e445c95ddb514840f63fbb1d12.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d7ac5396c5ea442e0364b50c1db3d2da.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bf29d07c3751c41ab3503065a5a5052e.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/3/6/b45ce535-d349-4989-9607-e7523d5a3050.png?resizew=388)
(1)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ec82279b14a119057fdd78b85d63e669.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3d2c15801fee2405573677484f5dcfa4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/12a4bddf1ea3c5d37f2233a4821909e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f3aace91caec728e174daec29a3568ae.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/48f3c9abbd78e9a6840ee5f30381daac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
您最近一年使用:0次