已知AB,AC分别是平面
的垂线和斜线,BC是AC在
内的射影,
且
.求证:
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e170f206fdbbd834aad7580c727e2cc6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e170f206fdbbd834aad7580c727e2cc6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1754786a3367aca3da18ee3316e5b968.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3777318aa3fbdee09cfeeea971e8fcf7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c95e692badf11ca5ac25104a166f4467.png)
更新时间:2023-10-05 09:22:10
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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
|
容易
(0.94)
解题方法
【推荐1】已知正方体
的棱长均为1.
(1)求
到平面
的距离;
(2)求平面
与平面
之间的距离.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b3da8c338342e38c9aa3f274c053fd5b.png)
(1)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3953cec61ac602ce5eb59b7912352179.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cc5bef4c4586630701fae5fa141c8818.png)
(2)求平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cc5bef4c4586630701fae5fa141c8818.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/43713ea7ad8151c6d035f9c7c63996d0.png)
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解答题-证明题
|
容易
(0.94)
解题方法
【推荐2】证明“平面与平面平行的判定定理”:同一个平面内有两条相交直线与另一个平面平行,则这两个平面平行.
已知:
,
,
,
,
.
求证:
.
已知:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a0e5acb08c1dd5f53d8ad43d53acb199.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5475e10ea3f37788e680395999037a00.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60750b5eab6344496e925eb603cab46a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a4d6a7aec04e1d5768ef830b534460a7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6b330d69a949d9b55f4b6f18f47e0a37.png)
求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/35f747152f006301e03b643afb80195c.png)
您最近一年使用:0次
解答题-问答题
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容易
(0.94)
名校
【推荐3】如图,在长方体
中,点
,
分别是
,
的中点,
,
.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/7/f7200460-675c-4a4d-a600-8bf007c053cd.png?resizew=169)
(1)求二面角
的余弦值;
(2)在线段
上是否存在点
,使得
平面
?若存在,求出
的值;若不存在,请说明理由.
![](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/3ee8456443402a25b1e25d35ff7e1c98.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e6155f82a6f64b20085976cea9b64193.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/21ea52361458ce2e49ed0fe99d8e6c02.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/7/f7200460-675c-4a4d-a600-8bf007c053cd.png?resizew=169)
(1)求二面角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/edd0a3b418f3b1ae176d2e9c5b4987de.png)
(2)在线段
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/394c5d2f55221975503be8aa18022480.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7767d492158189b23af332a8016ed37d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ebce46aeb97373353179e5669365fa4a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/52770ebb8599c8cfc28a8d1ebd6724d7.png)
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