如图,在正方体
中,点
是线段
的中点,点
是线段
上的点,若
平面
,试确定点
的位置,并说明理由.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6e09725691ee7851f54c0dee86b2bf55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54a5d7d3b6b63fe5c24c3907b7a8eaa3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e26d9636ad77369535852c6e4493446a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7592c4f01c8e06c7ee90df5b9413a9f5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5f96c673a2381f118ea2d3efc0bca1f3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54a5d7d3b6b63fe5c24c3907b7a8eaa3.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/1/13/148ad2a3-2e28-4349-9966-0fb4ca4da1bf.png?resizew=165)
20-21高二·全国·课后作业 查看更多[2]
更新时间:2021-09-24 10:43:23
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【知识点】 空间位置关系的向量证明
相似题推荐
解答题-问答题
|
较易
(0.85)
解题方法
【推荐1】如图,四棱锥
中,
平面
,四边形
是菱形,
,
,点
,
分别在棱
,
上,且
.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/12/a610ca0d-f308-464f-8a68-8bbab779993f.png?resizew=233)
(1)证明
平面
;
(2)求四棱锥
的体积.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0585b6c0f156eecf9662b9846d4eb693.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5a1b49f64e0065edad868b25e9fcada3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f1a572636ed4d26d323092ff0fc06f42.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e642f967bccda05833861a77cd277fef.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/48f3c9abbd78e9a6840ee5f30381daac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6aa2b51500bc0c0778a2b8af6d9539cb.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/12/a610ca0d-f308-464f-8a68-8bbab779993f.png?resizew=233)
(1)证明
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/373f735f0f04d11f1951eaef1bb78b6a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/134ef0b1a2669a09f05bd4dc2496f706.png)
(2)求四棱锥
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3c7bdd16146a583d93cbe21cf0e431ae.png)
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解答题-证明题
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较易
(0.85)
【推荐2】在正三棱锥PABC中,三条侧棱两两互相垂直,PA=PB=PC=3,G是△PAB的重心,E,F分别为BC,PB上的点,且BE∶EC=PF∶FB=1∶2.求证:平面EFG⊥平面PBC.
您最近一年使用:0次