定义空间中既有大小又有方向的量为空间向量.起点为
,终点为
的空间向量记作
,其大小称为
的模,记作
等于
两点间的距离.模为零的向量称为零向量,记作
.空间向量的加法、减法以及数乘运算的定义与性质和平面向量一致,如:对任意空间向量
,均有![](https://staticzujuan.xkw.com/quesimg/Upload/formula/53bcfdf754e71318fb8329b8e7c09264.png)
,
,
;对任意实数
和空间向量
,均有
;对任意三点
,均有
等.已知体积为
的三棱锥
的底面均为
,在
中,
是
内一点,
.记
.
(1)若
到平面
的距离均为1,求
;
(2)若
是
的重心,且对任意
,均有
.
(i)求
的最大值;
(ii)当
最大时,5个分别由24个实数组成的24元数组
满足对任意
,均有
,且对任意
均有
求证:
不可能对任意
及
均成立.
(参考公式:![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c082be7f93f355e1ca70588a4a89aead.png)
)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a18722354086c42e62334983fc50eb6a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cd3b9e816b14051f785aa5aae72b8eed.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/28fde0a8b4ec1e2fff42cee3fc54c0f9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/28fde0a8b4ec1e2fff42cee3fc54c0f9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/49da589810153e2ec39ed656a2b61f4b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/00442d96d695db2c58bf1fb7165fca94.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b12de8a4f788ff23d36e74c811354779.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2e12e95f703ad30ab9a3d38376830989.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/53bcfdf754e71318fb8329b8e7c09264.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ea3ff5e2f25dfebafaf8db07712ff706.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ff47a4801df7bc7bce1cb52327a7b174.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f8e0a953946d9e878aa017c7f24ffb40.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/df64046e91b047037f19e4032e3b6de3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/64c5562bd4d1b54424330cb6329cd79d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0714b48d55f6b0854fb90a4255bc49c8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d6fa157b4f65f3a9aa1f7f82de02e99e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2e1e19465c82977a26ca6900622ee1bc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/718ba76bf48024ca425948e470e60042.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c761455094dc4913de76122017a243dc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e48ac6b0dda0647d7dad3287ce4ad258.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d131fd570dc36b912396dc2dd06405c8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f4aeda1e642ce85f1c0394bc419bda8e.png)
(1)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f49f84442a1b38f27ac977214cd4b688.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bef5239ddbb0972700ce01daf9ee7cf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/be54e84508decfcce6d2fcbe6c8c1a92.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/acc290b44635265137fdf13146b6a6d9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/902a402a179a09f74f2391fb5cb4ae6e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/247daad150250fc13a230d5375adda93.png)
(i)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/be54e84508decfcce6d2fcbe6c8c1a92.png)
(ii)当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/be54e84508decfcce6d2fcbe6c8c1a92.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ab39849dc21c8c68cd5cde0911d5db23.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a61e6011a0717ef57516821d0407a656.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/aae3155971b2bb3c9d68b43e14b7186f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6ffe9f4e3243bd760835af03fa7ffe1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e8c053ebe33366203ad0eca474760118.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3d05f59bfd6b1f55920e73653bf87a46.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6ffe9f4e3243bd760835af03fa7ffe1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/db09e9844b90e46a6f2f5a710b6a3451.png)
(参考公式:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c082be7f93f355e1ca70588a4a89aead.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e2343b61be295955a2b9baea86202f32.png)
更新时间:2024-06-13 15:05:09
|
相似题推荐
解答题-问答题
|
困难
(0.15)
名校
【推荐1】如图①所示,长方形
中,
,
,点
是边
的中点,将
沿
翻折到
,连接
,
,得到图②的四棱锥
.
的体积的最大值;
(2)若棱
的中点为
,求
的长;
(3)设
的大小为
,若
,求平面
和平面
夹角余弦值的最小值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3f4aca5534bce25acaeb7379deed8f8f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fcd0ced286a0fbc7e4862f8147264277.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d78abbad68bbbf12af10cd40ef4c353.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f7f9fba8a4098c1a0515286eb8d616dc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d50703c46b6153945d718b198f03b4b5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4fb62dd4766d11cfec3aee092b99e40c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d2be49c37e30a3ced0364c3e74d8c687.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/48f3c9abbd78e9a6840ee5f30381daac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ec53c9cc69c2e3943ec8df5d5b5d44c7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ec53c9cc69c2e3943ec8df5d5b5d44c7.png)
(2)若棱
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d2be49c37e30a3ced0364c3e74d8c687.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54a5d7d3b6b63fe5c24c3907b7a8eaa3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/167d31eb8432b5c0364316e5048c23dd.png)
(3)设
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/212e8c352c4d9b022a057d7d7fa7dd14.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c24095e409b025db711f14be783a406c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b67c89ceb040588c165ad7a8030906c7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c745df4f226027778d5fe45b6501b822.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e7b7c83470489253394bd288d7c920df.png)
您最近一年使用:0次
解答题-问答题
|
困难
(0.15)
名校
解题方法
【推荐2】我们把和两条异面直线都垂直相交的直线叫做两条异面直线的公垂线.如图,在菱形
中,
,将
沿
翻折,使点A到点P处.E,F,G分别为
,
,
的中点,且
是
与
的公垂线.
(1)证明:三棱锥
为正四面体;
(2)若点M,N分别在
,
上,且
为
与
的公垂线.
①求
的值;
②记四面体
的内切球半径为r,证明:
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f945a69cf7e8213e50622125cde652f5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ab2a2834d80ff574e79eae8ca8d4e94f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d40b319212a7e7528b053e1c7097e966.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d40b319212a7e7528b053e1c7097e966.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e0629ce42392a7fe9be21d25c39c3e64.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c63e36329f5e0979f5ee776ac5d06327.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e0629ce42392a7fe9be21d25c39c3e64.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/7/7/36d7309a-d789-4b0d-bbdc-a09e1456bdf9.png?resizew=341)
(1)证明:三棱锥
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08a9ec3b527947cad9caa4537e0cb7e7.png)
(2)若点M,N分别在
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fc5adb5eb60ae4435a12d93854066298.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411461db15ee8086332c531e086c40c7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fc5adb5eb60ae4435a12d93854066298.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
①求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/51583e34d76abf46a39b56014a536208.png)
②记四面体
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/922b1e3f3948b044ff8f53af2aa1f038.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/45acf3747141ec164fcf0dff92439fd1.png)
您最近一年使用:0次
【推荐3】如图,四棱锥
中,
平面
,四边形
是直角梯形,其中
,
.
.
![](https://img.xkw.com/dksih/QBM/editorImg/2024/1/25/e1eb0158-b80b-4a2e-a635-1e2f881334e0.png?resizew=189)
(1)求异面直线
与
所成角的大小;
(2)若平面
内有一经过点
的曲线
,该曲线上的任一动点
都满足
与
所成角的大小恰等于
与
所成角.试判断曲线
的形状并说明理由;
(3)在平面
内,设点Q是(2)题中的曲线E在直角梯形
内部(包括边界)的、一段曲线
上的动点,其中G为曲线E和
的交点.以B为圆心,
为半径的圆分别与梯形的边
交于
两点.当
点在曲线段
上运动时,求四面体
体积的取值范围.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0585b6c0f156eecf9662b9846d4eb693.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ccd4fd4b7a4d6b8ca0c5827c055a9ce7.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/9536a2be7b84612f45cc875a00c5a5d0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/34e0a957a55460c72673c0f2ee90dbb3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/62d93b04d2343e39ba5bfc9992c06175.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2024/1/25/e1eb0158-b80b-4a2e-a635-1e2f881334e0.png?resizew=189)
(1)求异面直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/48f3c9abbd78e9a6840ee5f30381daac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
(2)若平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/acc290b44635265137fdf13146b6a6d9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7a5f1641947153c80b987320885a2b57.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/48f3c9abbd78e9a6840ee5f30381daac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
(3)在平面
![](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/abf80148409afb32ced0b4f59f1ba709.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9e52a8f07834cbbbe4224962672fbbb2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cb6ede9761b5b90f8dc137708e1ee90f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3355e2fa0ac6c675f02ee36c3ced4f2d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e6670479a0083dd2dfd5ad55b47b1ab6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/acc290b44635265137fdf13146b6a6d9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f8e5f736b1195fef1d2d300168a795f1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/543c3b2beb11fbc94d66570bfbed3ea8.png)
您最近一年使用:0次