如图,三棱柱
中,侧棱
底面
,且各棱长均相等.D,E,F分别为棱
的中点.
![](https://img.xkw.com/dksih/QBM/2021/7/6/2758394252189696/2769952429891584/STEM/216801e04a96454d87d9acd6e6f5f90d.png?resizew=182)
(1)证明:
平面
;
(2)求直线
与直线
所成角的正弦值.
![](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/7bef5239ddbb0972700ce01daf9ee7cf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2145212ffad3fbbea528d4c167c3424a.png)
![](https://img.xkw.com/dksih/QBM/2021/7/6/2758394252189696/2769952429891584/STEM/216801e04a96454d87d9acd6e6f5f90d.png?resizew=182)
(1)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/06222ee533c2484ab25321a6abbf98cb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/74bca84ad86c648d3bb20c8909c8da3f.png)
(2)求直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/49b50357a6545cae8348e3059312f520.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/11ddc92d84d188c66b435664a7e7b5a4.png)
20-21高一下·湖南邵阳·期末 查看更多[2]
更新时间:2021-07-22 22:25:33
|
相似题推荐
【推荐1】如图所示,在棱长为2的正方体
中
,
分别是
,
的中点.
![](https://img.xkw.com/dksih/QBM/2021/10/7/2824218957651968/2829309225779200/STEM/dbe05a7d-ba36-4893-b3a9-453f39cd594d.png?resizew=275)
(1)异面直线
与
所成的角的大小;
(2)求三棱锥
的体积.
![](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/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d88bf46ad08f9677c37eed1d0369329.png)
![](https://img.xkw.com/dksih/QBM/2021/10/7/2824218957651968/2829309225779200/STEM/dbe05a7d-ba36-4893-b3a9-453f39cd594d.png?resizew=275)
(1)异面直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9ce1b066f8869d0ff4513f7a99745125.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/408871c2b71ef88d6f556ce53cf73cc9.png)
(2)求三棱锥
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b70d05c03d14c3bd6f61746e556c1f85.png)
您最近一年使用:0次
解答题-问答题
|
较易
(0.85)
名校
【推荐2】已知圆锥的体积为
,底面半径
与
互相垂直,且
;
是母线
的中点.
![](https://img.xkw.com/dksih/QBM/2020/11/27/2601870764351488/2605516177252352/STEM/9c2fc2e5-070a-4360-bfee-762ec8712f71.png?resizew=235)
(1)求圆锥的表面积
(2)求异面直线
与
所成角的大小(结果用反三角函数表示)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/86ebba6ed1add0fe647c0226614b9290.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ef4113c492885ba7c47fe42ac792578f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b90e0f35eda1a729fed485f83da5ea9d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/11f16e77b039842ae40a4b04c527655a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e7b5e290c6b2c5508a3bf6117afbf7e1.png)
![](https://img.xkw.com/dksih/QBM/2020/11/27/2601870764351488/2605516177252352/STEM/9c2fc2e5-070a-4360-bfee-762ec8712f71.png?resizew=235)
(1)求圆锥的表面积
(2)求异面直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/18e5ef91fb27dd684a27ae7f1993cfba.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bd33764ff4efddfe11a98a609753715c.png)
您最近一年使用:0次
解答题-证明题
|
较易
(0.85)
【推荐1】如图,在直三棱柱
中,侧面
侧面
分别为
的中点,
;
![](https://img.xkw.com/dksih/QBM/editorImg/2022/7/4/e9a31ec4-910f-458a-9bfc-9c0ddc6a30fc.png?resizew=308)
(1)求证:直线
面
;
(2)求异面直线
与
所成角的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/42d3a82b8e587ee890467835bc4e854c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0671b4776e142e17a79af5b3f0378ef7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/61faf985f63573068ea527261563fe76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/de0d28544dd3bc8a10b44c5a132781d3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/75cc75c4de42f97bf982953d54bfbff7.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/7/4/e9a31ec4-910f-458a-9bfc-9c0ddc6a30fc.png?resizew=308)
(1)求证:直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2f3980ea23301ddd8d3a773f6a3dfaf8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6684d8fe0d6da7564247e47b948e3997.png)
(2)求异面直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4a2cda9e5690d90d24c318895db59a45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7785afeeaf274892253d04b4f693b367.png)
您最近一年使用:0次
解答题-问答题
|
较易
(0.85)
名校
解题方法
【推荐2】如图,在正三棱柱
中,点
为
的中点,
.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/1/28/619a9ae4-925d-4d4f-af83-268918fa784c.png?resizew=142)
(1)证明:
平面
;
(2)求直线
到平面
的距离.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/42d3a82b8e587ee890467835bc4e854c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e26d9636ad77369535852c6e4493446a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e4bb9bdc8210cadb211e5e962191f4aa.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/1/28/619a9ae4-925d-4d4f-af83-268918fa784c.png?resizew=142)
(1)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/002cc6a0373255f39172cdee62fb6b39.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/41104641f3e2260d00aeadf8fb8a078a.png)
(2)求直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/41104641f3e2260d00aeadf8fb8a078a.png)
您最近一年使用:0次
解答题-证明题
|
较易
(0.85)
名校
【推荐3】如图,在四棱锥
中,平面
平面
,
.且
.
![](https://img.xkw.com/dksih/QBM/2021/6/1/2733761570119680/2733786617774080/STEM/89e96ad714a041359add5bb20aa29dd0.png?resizew=247)
(I)求证:
平面
;
(Ⅱ)求证:
平面
;
(Ⅲ)求二面角
的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0585b6c0f156eecf9662b9846d4eb693.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/93edc7bb513f40a89173121c8570cd65.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8547b1598b860886c95458ed6d913019.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/55a68f6380a3d695e88a67bead50ec4a.png)
![](https://img.xkw.com/dksih/QBM/2021/6/1/2733761570119680/2733786617774080/STEM/89e96ad714a041359add5bb20aa29dd0.png?resizew=247)
(I)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/307807ee10071bafbe922eb18d2517d7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/80f747eb5b2d21c9de962cbfd4ec4bb7.png)
(Ⅱ)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/21f9157fce2a8339d281178c7c0bccbe.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/852aabd89edffc1b94344ff3f1f31ccd.png)
(Ⅲ)求二面角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b33b7213d99a817bff19bcf740a0697c.png)
您最近一年使用:0次