如图,在平行六面体
中,以顶点A为端点的三条棱长度都为2,且两两夹角为
.
![](https://img.xkw.com/dksih/QBM/editorImg/2024/3/18/b02e7d9b-0ead-4aa2-b582-d0c88c36b6f3.png?resizew=174)
(1)求
的长;
(2)求
与
所成角的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6e09725691ee7851f54c0dee86b2bf55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/be6a6301878fed2a01413020b27310a5.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2024/3/18/b02e7d9b-0ead-4aa2-b582-d0c88c36b6f3.png?resizew=174)
(1)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/87470f6137cb2d3755bb229ab0dda909.png)
(2)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e9146c5f1be07949fe8278022f4a9a65.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2b680f91c4a693cc9ab2c23f2e9114ce.png)
更新时间:2021-07-22 19:09:18
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解答题-问答题
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【推荐1】在空间直角坐标系
中,
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(1)求点
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(2)若
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(1)求点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/df64046e91b047037f19e4032e3b6de3.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/58ac6979adfa3b30c6067a9fdfd49f08.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/df64046e91b047037f19e4032e3b6de3.png)
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【推荐2】已知四棱锥
的底面
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![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
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解题方法
【推荐1】如图,棱长为2的正方体中,E,F分别是
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![](https://img.xkw.com/dksih/QBM/editorImg/2022/10/24/5ecb8a2e-e5e5-4f11-8a07-7e5e25c00857.png?resizew=179)
(1)求异面直线EF和
所成角的余弦值;
(2)求FH的长.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/161f651ef002ac85870d46b04347b54f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dcaa043eed56b55c053fd9923b1d4bb3.png)
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(1)求异面直线EF和
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f380fae9201fb0f46a3df1062a2bcdf2.png)
(2)求FH的长.
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解题方法
【推荐2】如图,在三棱锥VABC中,顶点C在空间直角坐标系的原点处,顶点A,B,V分别在x,y,z轴上,D是线段AB的中点,且AC=BC=2,∠VDC=
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