如图,在几何体
中,底面
是边长为2的正三角形,
平面
,
,且
,
是
的中点.
![](https://img.xkw.com/dksih/QBM/2021/12/4/2865447135051776/2866591153471488/STEM/09dca0a8-2eb9-439b-92cb-fc54ef28bebb.png?resizew=182)
(1)求证:
平面
;
(2)求异面直线
与
所成的角.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/42d3a82b8e587ee890467835bc4e854c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5845ccc0d735dc14c92a8926d9b1def6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bef5239ddbb0972700ce01daf9ee7cf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/36723bd074d43a8c98d9bd416020042c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fe92f03a4be8e01673d1fe99354e56d8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://img.xkw.com/dksih/QBM/2021/12/4/2865447135051776/2866591153471488/STEM/09dca0a8-2eb9-439b-92cb-fc54ef28bebb.png?resizew=182)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/932a04304f2d4975955d4baabb2deeea.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/99b16cff607cdc2d69afc70dc778acbb.png)
(2)求异面直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4eedae8d316c76e3d0b451256de03fb9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/56f7ba05c54b3de1f4378f7c8eb58328.png)
更新时间:2021-12-06 11:17:32
|
相似题推荐
解答题-证明题
|
适中
(0.65)
解题方法
【推荐1】如图,多面体
是将一个平行六面体
截去三棱锥
后剩下的几何体,P为三角形
的重心,Q为
的中点.四边形ABCD是边长为1的正方形,且
,
.
(1)求异面直线BC与
所成角的大小;
(2)求证:直线
平面
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9164d4bc2ff3ae9d739f7056bfe4d6df.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6e09725691ee7851f54c0dee86b2bf55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/99516e53f1ff2599ed3296963d2a51d5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e86eec8526479272d15bb3b171a46de0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2777840758e70e7dbbc18cef8f3d6d2b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/92535536bd3c2761724fd058427f95a8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7ce64c7cf095a20894e9ddd0d95992a9.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/8/28/2148e17d-1702-4c43-9a89-163c777ec2ef.png?resizew=220)
(1)求异面直线BC与
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/16d41164f8a9f6fe32a9364f18f168dd.png)
(2)求证:直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f844a41f79ea2b231b326f8633beac50.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6fc56633186b0e76a5a9d7298d8aac7e.png)
您最近一年使用:0次
解答题-问答题
|
适中
(0.65)
名校
解题方法
【推荐2】如图,在三棱锥
中,
,
,
分别为
的中点,
为线段
上一点.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/25/1dd4384e-5eeb-48f0-8d36-6113994a72e9.png?resizew=188)
(1)求直线
和
所成角的余弦值;
(2)当直线
平面
时,求四棱锥
的体积.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/891579e7c231584a8e16b8eeff79888e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/aecee82ab179207056c1e1f06e97af93.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/82db4fedaabaf9ded8584273d1a2be9c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ad056c25c0fdcbcc765eb5cbc6093f2b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/94c905599045694c50d401bfc78c394f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/895dc3dc3a6606ff487a4c4863e18509.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d40b319212a7e7528b053e1c7097e966.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/25/1dd4384e-5eeb-48f0-8d36-6113994a72e9.png?resizew=188)
(1)求直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/85c4bdfb0db1e31e8459df1d15f9ab55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6aa2b5e09f8ec785c59900a529390a02.png)
(2)当直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c372d059202ec388960b125d4a87dc84.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b46a7e819a5ed0b789f1f06bb0076422.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/efd01843371e9b744e639c1472325b26.png)
您最近一年使用:0次
解答题-证明题
|
适中
(0.65)
【推荐3】在正方体
中
分别为
的中点.
![](https://img.xkw.com/dksih/QBM/2016/11/11/1573142612000768/1573142618333184/STEM/3dc6a5798bdb482388bb9f19370fabc1.png?resizew=158)
(1)求证:
平面
;
(2)求异面直线
与
所成的角.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f72f3c822c5af2aa53148d7ad47c5601.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/468cb8c6fe30c22d91251572f194d134.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6ea4db7414d2a93595da92dd7636f06d.png)
![](https://img.xkw.com/dksih/QBM/2016/11/11/1573142612000768/1573142618333184/STEM/3dc6a5798bdb482388bb9f19370fabc1.png?resizew=158)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1399e7ae0b2decaafc62a5cdffb15522.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b2bf9ef324f1289e205e29fed105c38e.png)
(2)求异面直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c2e47999eaa20cee553c86500f909556.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/31e55e398e8520d8a36fb5a625a085b8.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①,在平面五边形
中,
是梯形,
,
,
,
,
是等边三角形.现将
沿
折起,连接
,
得到如图②的几何体.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/22/d020cfad-1583-48e1-ae8f-65b3c1e4ceb6.png?resizew=331)
(1)若点
是
的中点,求证:
平面
﹔
(2)若平面
平面
,求四棱锥
的体积.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9142a8490de14a87eda628ffa7e28982.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f571396be1aa4a8914a66f7d7abd6381.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5827a006e69fc21a86abe63f86b7e2c3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/68b40d0d2f3cdd8981bb792ad87efb42.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/45acdbac251ca6b76a166c1242e71df9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a25c28359f8d8da9eaf4672a6cf8ae4f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a25c28359f8d8da9eaf4672a6cf8ae4f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ccaee8f228ff24e7c89879bb5b999cf2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1fc56c77464a17a1e97b568762a3e2c6.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/22/d020cfad-1583-48e1-ae8f-65b3c1e4ceb6.png?resizew=331)
(1)若点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/21037e170bdbb322558e79c40c00b454.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5865d488a9cf1181016fd2e866177cdd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c09afc70f448545336304333d5b5658b.png)
(2)若平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4d28c625d7ac6878957facc8274d459c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/80c753cb1eb73fd8d136d00462970797.png)
您最近一年使用:0次
解答题-证明题
|
适中
(0.65)
解题方法
【推荐2】如图,在四棱锥
中,底面
为正方形,
平面
,已知
,
为线段
的中点.
(1)求证:
平面
;
(2)求四棱锥
的体积.
![](https://img.xkw.com/dksih/QBM/2014/5/13/1571715782893568/1571715788595200/STEM/1c263f5405184513ad6fd7d32ae277ad.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://img.xkw.com/dksih/QBM/2014/5/13/1571715782893568/1571715788595200/STEM/9294d0ff306b40a188f32f1d9d2d7202.png)
![](https://img.xkw.com/dksih/QBM/2014/5/13/1571715782893568/1571715788595200/STEM/98f9b79c28ba4a28b2b60222aef2ebcd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e2e50f0d02d0bd51ae361d276ed9dea4.png)
![](https://img.xkw.com/dksih/QBM/2014/5/13/1571715782893568/1571715788595200/STEM/05b949e8a1b244b5b3a66b245efe8e2d.png)
![](https://img.xkw.com/dksih/QBM/2014/5/13/1571715782893568/1571715788595200/STEM/316e391450bb46df9c087bb63c6ac8b3.png)
(1)求证:
![](https://img.xkw.com/dksih/QBM/2014/5/13/1571715782893568/1571715788595200/STEM/dafdadfa643548719594ebe365e31b5a.png)
![](https://img.xkw.com/dksih/QBM/2014/5/13/1571715782893568/1571715788595200/STEM/dc20dd6e8e1c48f3853a7fa6e6361473.png)
(2)求四棱锥
![](https://img.xkw.com/dksih/QBM/2014/5/13/1571715782893568/1571715788595200/STEM/1c263f5405184513ad6fd7d32ae277ad.png)
![](https://img.xkw.com/dksih/QBM/2014/5/13/1571715782893568/1571715788595200/STEM/4307671f62d04dc89c4db16c3e9d917e.png)
您最近一年使用:0次
解答题-问答题
|
适中
(0.65)
【推荐3】如图,在斜三棱柱
中,
,
,
,侧面
与底面ABC所成的二面角为
,E,F分别是棱
,
的中点.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/1/52089085-d0f2-4481-a506-f873900173b0.png?resizew=186)
(Ⅰ)证明:
平面
;
(Ⅱ)求直线
与底面ABC所成的角的大小.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/42d3a82b8e587ee890467835bc4e854c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/521e771f98c17242d43c78d511ba7134.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/047dc9795efa99b6fb9fdf9778085dab.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4b96a62aa7299af759c45381f8532c9d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5f96c673a2381f118ea2d3efc0bca1f3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a6c0927afc571a7c966c98192040979e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/56f7ba05c54b3de1f4378f7c8eb58328.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4a696a182fff038a86b2bbe8ca099442.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/1/52089085-d0f2-4481-a506-f873900173b0.png?resizew=186)
(Ⅰ)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d560542b646924eaf577480ac73281b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ad0bddbc7364c8fd7247bd164bdfb645.png)
(Ⅱ)求直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3ee8456443402a25b1e25d35ff7e1c98.png)
您最近一年使用:0次