如图所示,已知
是△
所在平面外一点,
,
求证:
在面
上的射影
是△
的垂心.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c95b6be4554f03bf496092f1acdfbb89.png)
![](https://img.xkw.com/dksih/QBM/2016/11/29/1826268635201536/1826268635824128/STEM/61df6ecb8aec4a1eafe12e9dc9e9a5d9.png)
![](https://img.xkw.com/dksih/QBM/2016/11/29/1826268635201536/1826268635824128/STEM/77c6f2490ec94f159b59580995fcdf7e.png)
求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c95b6be4554f03bf496092f1acdfbb89.png)
![](https://img.xkw.com/dksih/QBM/2016/11/29/1826268635201536/1826268635824128/STEM/61df6ecb8aec4a1eafe12e9dc9e9a5d9.png)
![](https://img.xkw.com/dksih/QBM/2016/11/29/1826268635201536/1826268635824128/STEM/a21decf80eb94e88be638db879911aeb.png)
![](https://img.xkw.com/dksih/QBM/2016/11/29/1826268635201536/1826268635824128/STEM/61df6ecb8aec4a1eafe12e9dc9e9a5d9.png)
![](https://img.xkw.com/dksih/QBM/2016/11/15/1836136225628160/1826268635824128/STEM/5e490876-bfc5-4f49-9cb9-bee758462548.png)
2016高二·全国·课后作业 查看更多[1]
(已下线)同步君人教A版选修2-1第三章3.1.3空间向量的数量积运算
更新时间:2017-11-27 15:35:57
|
【知识点】 空间向量数量积的应用
相似题推荐
解答题-问答题
|
适中
(0.65)
解题方法
【推荐1】如图,已知四面体ABCD的所有棱长都等于1,E,F,G分别是棱AB,AD,BC的中点.
(1)求
;
(2)求直线GE,GF夹角的余弦值.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/11/10/dcd7d256-a298-401a-ac35-b4ad197e2347.png?resizew=141)
(1)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/840f34999a34f2a2c5745390b32bea50.png)
(2)求直线GE,GF夹角的余弦值.
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解答题-证明题
|
适中
(0.65)
解题方法
【推荐2】如图,
内接于
,
为
的直径,
,
,
,且
平面
,
为
的中点.
平面
;
(2)求异面直线
与
所成的角;
(3)求点
到平面
的距离.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3d97cdc586744d208b6f69c9813af977.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3d97cdc586744d208b6f69c9813af977.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fc34db5860990e51ba31edc8cdd077c2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/07160f14b3b453bebb64cb2bf96dc85a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/de8cc58ef27567f0ab06eb1012aec330.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/97f30533da2e1d2a958dc906c37eba9d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bef5239ddbb0972700ce01daf9ee7cf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/39282bdf319f30d7bc261e2e3ab3b1e4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7abd284f76d9f5769bc189508ce2572b.png)
(2)求异面直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/85c4bdfb0db1e31e8459df1d15f9ab55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
(3)求点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/500df0e782bb081e608f4bc1d576afcf.png)
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