如图,在平行六面体
中,
,
,
.用向量法 解下列问题:
![](https://img.xkw.com/dksih/QBM/editorImg/2023/12/30/5cb11c55-bc0f-4bea-85db-1259fb30f49c.png?resizew=165)
(1)求
长度;
(2)求证:
;
(3)若点M,N分别在直线
和
上运动,当
且
时(MN为公垂线段,这样的MN只有一条),求MN的长度.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b3da8c338342e38c9aa3f274c053fd5b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/067613594cca07e73993d85045e8964f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d262480ffb55b7617f44b63f130c154a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/92535536bd3c2761724fd058427f95a8.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/12/30/5cb11c55-bc0f-4bea-85db-1259fb30f49c.png?resizew=165)
(1)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6eb97aff0960e2640314888a38e7169c.png)
(2)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b219a74a1ce5a2b22c36d8de1e21ff91.png)
(3)若点M,N分别在直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/82b25f3ea33cc08b1e2a0d9c3a9dccaf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6eb97aff0960e2640314888a38e7169c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/df93277710b49a14d6ff1b9d5e99260c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/722ba1f4d15c9bf91ef3de85202e9406.png)
更新时间:2023-12-30 15:50:51
|
相似题推荐
解答题-问答题
|
适中
(0.65)
【推荐1】在平行六面体
中,
,
,
,
,
,
,
,
分别为
,
的中点.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/1/9/c99a8122-6dae-4af8-8340-024d4c12f5d0.png?resizew=219)
(1)
构成空间的一个基底,用它们表示
,
,设
,
,
.
(2)求
与
的夹角.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6e09725691ee7851f54c0dee86b2bf55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3d2c15801fee2405573677484f5dcfa4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fc11331a7b2d2619b40ee6d34c3bd620.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1f3e58edd1f900ca82bb2a3058293f52.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ea4f5eec0addba78f2e0cdfb7ecc59a6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b29e8a1eefb6776168969a1155c9e9c5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c7276aacfe84451993bb85d15e946e5e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54a5d7d3b6b63fe5c24c3907b7a8eaa3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5fbafedc202bd0d86c4dfdece9f8f4fe.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ab35850dbc661ded6456b70767cc6cd0.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/1/9/c99a8122-6dae-4af8-8340-024d4c12f5d0.png?resizew=219)
(1)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6f8d2051594370095e72e173fd95888a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4dd4b9ad667f6da79bc3a5737cbc1eee.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e650df8a77daeaa4b8eb3476c35317f4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4e7a93a1399ff7a2bde342652479241b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d3b54aa2b7f9adf409f0ce8e00615432.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8a75216f7a68428fb8dd41221e854117.png)
(2)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/24bb49fdc6b6bbb2449fdf8a0de769d3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411461db15ee8086332c531e086c40c7.png)
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【推荐2】棱长为2的正方体中,E,F分别是
,DB的中点,G在棱CD上,且
,H是
的中点.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/3/23/1d330ce8-7f95-455c-98c7-176482ed301c.png?resizew=154)
(1)求
.
(2)求FH的长.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/22adbc0da438220f9cace11b629d799b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6de2ee944c8c3476e3014050f0e36199.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2fec5bd77cfc1313bc200480cc66c766.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/3/23/1d330ce8-7f95-455c-98c7-176482ed301c.png?resizew=154)
(1)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/615b0e304bc6bf27ad32db1a924fec23.png)
(2)求FH的长.
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解答题-问答题
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(0.65)
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解题方法
【推荐1】在直三棱柱
中,
,E,F分别为线段
的中点.
![](https://img.xkw.com/dksih/QBM/2022/4/8/2953611970338816/2953988399284224/STEM/77d748245857406bbfca17631e8cab40.png?resizew=188)
(1)证明:
平面
;
(2)若二面角
的大小为
,求三棱柱
的体积.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/42d3a82b8e587ee890467835bc4e854c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2fa92d4923a1d7142b9352fd9251b68a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/01c0c54d44c8281e02e88c70747c9751.png)
![](https://img.xkw.com/dksih/QBM/2022/4/8/2953611970338816/2953988399284224/STEM/77d748245857406bbfca17631e8cab40.png?resizew=188)
(1)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4a5f445af1ae136773cb338920552ff2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6ac61c24f99a4e466f1e2ea011893866.png)
(2)若二面角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ad2fa6425e73a7dce959dfa2d206a4cc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac1a63ab608517bb10aa036783dfb51f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/42d3a82b8e587ee890467835bc4e854c.png)
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解答题-证明题
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解题方法
【推荐2】如图,在四棱锥
中,底面ABCD是直角梯形,侧棱
底面ABCD,AB垂直于AD和BC,SA=AB=BC=2,AD=1,M是棱SB的中点.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/8/14/3831c363-9ad3-44fc-a9d6-de6b04004202.png?resizew=163)
(1)求证:
平面SCD;
(2)求平面SCD与平面SAB所成锐二面角的余弦值;
(3)设点N是线段CD上的动点,MN与平面SAB所成的角为
,求
的最大值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/faeb97acf19bd3b2c6c77c2814df4d2f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/10c83f8945042b9c8fb2fbdac9308d62.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/8/14/3831c363-9ad3-44fc-a9d6-de6b04004202.png?resizew=163)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9f33fa5152ba27f7b8a28890cefca219.png)
(2)求平面SCD与平面SAB所成锐二面角的余弦值;
(3)设点N是线段CD上的动点,MN与平面SAB所成的角为
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c24095e409b025db711f14be783a406c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/de7d5ef3a3d9a03be91135fc426d57cc.png)
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【推荐3】如图,在四棱锥
中,底面
为正方形,平面
平面
,
为棱
的中点,
,
.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/28/c1161d76-153f-404e-9010-efa47399ecc5.png?resizew=157)
(1)求证:
平面
;
(2)求平面
与平面
夹角的余弦值;
(3)求直线
到平面
的距离.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d02bd5cfe804460846423e77f72db10f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5cb3f9a5da641be35117fd35ba07a6aa.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ebbb79892c8cb8871a08437acc09bc80.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5cb3f9a5da641be35117fd35ba07a6aa.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/acc290b44635265137fdf13146b6a6d9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/365822bd3945e6a3e871ca979c84cc12.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/547f5dc6466478f509e31ab4a4fc5a34.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d001be02aec8fa6d094a80d0115430ff.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/28/c1161d76-153f-404e-9010-efa47399ecc5.png?resizew=157)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cb4564baf209de77802d46cda82995c5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5cb3f9a5da641be35117fd35ba07a6aa.png)
(2)求平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/118dcf2ba4fd9ffd61a17de2670c211c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5cb3f9a5da641be35117fd35ba07a6aa.png)
(3)求直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/30513ea48bc1ef3ae78adac83d894f14.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/118dcf2ba4fd9ffd61a17de2670c211c.png)
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解题方法
【推荐1】已知向量
满足
,且
.
(1)求向量
在向量
方向上的投影向量;
(2)求
的值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0b172cf8d898883d82e973f28c3c3a3e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/85200c186b0a512788f354c92a119888.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/53d04edd4fec534119ee31974fcf72ae.png)
(1)求向量
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7a2f4b1178f68bd147d1a2a6acd04435.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c94075193c11fe43f2396cff5a485054.png)
(2)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/26f87bd19071aea982ad6c1ae5170e91.png)
您最近一年使用:0次
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解题方法
【推荐2】已知向量
,
,
.
(1)若
,求
值;
(2)若向量
在
方向上的投影向量为
,求
的值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/81f4dcf415977dea53f52a85b6b82136.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/92b1305dff4fc89f3e8bc75fa7c258de.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ab00543b1f4647a7249fe5a4507e1ec1.png)
(1)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0b610fe3872cd8c1009b6a3e0111bacd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/df64046e91b047037f19e4032e3b6de3.png)
(2)若向量
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ed492f7b29166ba5c1f0023b05a439c5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/73a0b19e69be46452425916a0fcb49c9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2cef9c6d3fc0c7d3ec11c782fd106511.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/df64046e91b047037f19e4032e3b6de3.png)
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