名校
解题方法
1 . 对于空间向量
,定义
,其中
表示x,y,z这三个数的最大值.
(1)已知
,
.
①直接写出
和
(用含
的式子表示);
②当
,写出
的最小值及此时
的值;
(2)设
,
,求证:
;
(3)在空间直角坐标系
中,
,
,
,点Q是
内部的动点,直接写出
的最小值(无需解答过程).
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1b303ef66609858e8ab234b6dabccba4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2e382f70d741ee01c165391ce980155d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8a4461408813c1476a8a8073c83b8989.png)
(1)已知
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/23056c429159c0198f865ff11972d8df.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5e17d2355419564f6d9737295412b58c.png)
①直接写出
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9873960d64934875139754efbdfe951d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/13af5f843689a63bc176c2d2171b6a1d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/81dea63b8ce3e51adf66cf7b9982a248.png)
②当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/53168695826b0a33a23067b76173c7e5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/780ef5119f58f853ce9dd2b9176ffdde.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/81dea63b8ce3e51adf66cf7b9982a248.png)
(2)设
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/778ae4468d857c229073875e0ee0ce31.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6772fa3937b97d9ec3aec1ea2ea143b5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/95086cc97ef93f5166489b3bc47e1911.png)
(3)在空间直角坐标系
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d5e336d6ca2cae3d6e6c3810d7e521a4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1b32ab04dd852329d5918b177c199eee.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ee736aec4313d04a5921ed7e5800b3b7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6d04a00e46c1ffb335f73506041c66dc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/084fc7655647b596d07e80269d086e5a.png)
您最近一年使用:0次
名校
2 . 如图,
是等腰直角三角形,
都垂直于平面
,且
为线段
的中点.
(1)证明:
;
(2)若
平面
,垂足为
,求平面
和平面
夹角.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ff8ec9971ec0b23d98a847fdf171209d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bef5239ddbb0972700ce01daf9ee7cf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5365d59f410f35bc8e7fe548ca2d6f64.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2319a01218514917e446dfc807a625ff.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/11/8/acfe9831-05c2-469e-958a-5b4ee5c7d282.png?resizew=126)
(1)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/53c79c4d655d22f6b3e9826adc6df810.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7d0edb1508fc95765f3bb316bcb5252d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/065f7ff90e26ff382aa7b709955ad1b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/daf2f0df53aa68c9c334165034788166.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bef5239ddbb0972700ce01daf9ee7cf.png)
您最近一年使用:0次
3 . 如图,已知
、
、
、
、
、
、
、
、
为空间的
个点,且
,
,
,
,
,
,
.
![](https://img.xkw.com/dksih/QBM/2016/11/15/1836136229879808/1826268636012544/STEM/2022ebbeb0664162b3f84a7ed49038ac.png?resizew=167)
求证:(1)
、
、
、
四点共面,
、
、
、
四点共面;
(2)
;
(3)
.
![](https://img.xkw.com/dksih/QBM/2016/11/29/1826268635201536/1826268636012544/STEM/c8fa5b04e30e48868fe132789b807597.png?resizew=16)
![](https://img.xkw.com/dksih/QBM/2016/11/29/1826268635201536/1826268636012544/STEM/3066e7be6d7c4c518443aac35ebc6fc5.png?resizew=16)
![](https://img.xkw.com/dksih/QBM/2016/11/29/1826268635201536/1826268636012544/STEM/b91007e2ea5e433e95db20f4365af044.png?resizew=16)
![](https://img.xkw.com/dksih/QBM/2016/11/29/1826268635201536/1826268636012544/STEM/97903bb1c17f421d99f9d22a60f06e1a.png?resizew=16)
![](https://img.xkw.com/dksih/QBM/2016/11/29/1826268635201536/1826268636012544/STEM/04d375abd23446d49614ae0320e80084.png?resizew=17)
![](https://img.xkw.com/dksih/QBM/2016/11/29/1826268635201536/1826268636012544/STEM/b5a2daa15b914c598c2eab346ad7223e.png?resizew=16)
![](https://img.xkw.com/dksih/QBM/2016/11/29/1826268635201536/1826268636012544/STEM/33f3cc1423584e0dbcb2758c3e25432d.png?resizew=17)
![](https://img.xkw.com/dksih/QBM/2016/11/29/1826268635201536/1826268636012544/STEM/0b593aab85fb4dbcb2ebdf05a19793da.png?resizew=17)
![](https://img.xkw.com/dksih/QBM/2016/11/29/1826268635201536/1826268636012544/STEM/855db6b1d0d84981842248c6e4474b0e.png?resizew=19)
![](https://img.xkw.com/dksih/QBM/2016/11/29/1826268635201536/1826268636012544/STEM/0dbdef66d115422081bc2e5a32f48d7c.png?resizew=12)
![](https://img.xkw.com/dksih/QBM/2016/11/29/1826268635201536/1826268636012544/STEM/847f57351bde4581abef8a8eca1c6630.png?resizew=72)
![](https://img.xkw.com/dksih/QBM/2016/11/29/1826268635201536/1826268636012544/STEM/c6b86275082f489cbaca3001edb878c6.png?resizew=74)
![](https://img.xkw.com/dksih/QBM/2016/11/29/1826268635201536/1826268636012544/STEM/cba340111acb4e49b35a90810589fa18.png?resizew=77)
![](https://img.xkw.com/dksih/QBM/2016/11/29/1826268635201536/1826268636012544/STEM/ae8730bc42424af6af4187c0829e1322.png?resizew=115)
![](https://img.xkw.com/dksih/QBM/2016/11/29/1826268635201536/1826268636012544/STEM/f1055c0362da4a4fbde3e599db2ebaeb.png?resizew=116)
![](https://img.xkw.com/dksih/QBM/2016/11/29/1826268635201536/1826268636012544/STEM/3ef175e21b1b4b148b88a747da214799.png?resizew=37)
![](https://img.xkw.com/dksih/QBM/2016/11/29/1826268635201536/1826268636012544/STEM/4f3b0d4465694c178a6a044b9be25f3a.png?resizew=42)
![](https://img.xkw.com/dksih/QBM/2016/11/15/1836136229879808/1826268636012544/STEM/2022ebbeb0664162b3f84a7ed49038ac.png?resizew=167)
求证:(1)
![](https://img.xkw.com/dksih/QBM/2016/11/29/1826268635201536/1826268636012544/STEM/3066e7be6d7c4c518443aac35ebc6fc5.png?resizew=16)
![](https://img.xkw.com/dksih/QBM/2016/11/29/1826268635201536/1826268636012544/STEM/b91007e2ea5e433e95db20f4365af044.png?resizew=16)
![](https://img.xkw.com/dksih/QBM/2016/11/29/1826268635201536/1826268636012544/STEM/97903bb1c17f421d99f9d22a60f06e1a.png?resizew=16)
![](https://img.xkw.com/dksih/QBM/2016/11/29/1826268635201536/1826268636012544/STEM/04d375abd23446d49614ae0320e80084.png?resizew=17)
![](https://img.xkw.com/dksih/QBM/2016/11/29/1826268635201536/1826268636012544/STEM/b5a2daa15b914c598c2eab346ad7223e.png?resizew=16)
![](https://img.xkw.com/dksih/QBM/2016/11/29/1826268635201536/1826268636012544/STEM/33f3cc1423584e0dbcb2758c3e25432d.png?resizew=17)
![](https://img.xkw.com/dksih/QBM/2016/11/29/1826268635201536/1826268636012544/STEM/0b593aab85fb4dbcb2ebdf05a19793da.png?resizew=17)
![](https://img.xkw.com/dksih/QBM/2016/11/29/1826268635201536/1826268636012544/STEM/855db6b1d0d84981842248c6e4474b0e.png?resizew=19)
(2)
![](https://img.xkw.com/dksih/QBM/2016/11/29/1826268635201536/1826268636012544/EXPLANATION/8fe0f5e54a904f04abfa0fdf835415be.png?resizew=68)
(3)
![](https://img.xkw.com/dksih/QBM/2016/11/29/1826268635201536/1826268636012544/STEM/26aac0e0723242a8984e34736049ce88.png?resizew=76)
您最近一年使用:0次
2016高二·全国·课后作业
4 . 如图,已知
、
、
、
、
、
、
、
、
为空间的
个点,且
,
,
,
,
,
,
.
![](https://img.xkw.com/dksih/QBM/2016/11/15/1836136229879808/1826268636012544/STEM/2022ebbeb0664162b3f84a7ed49038ac.png?resizew=167)
求证:(1)
、
、
、
四点共面,
、
、
、
四点共面;
(2)
;
(3)
.
![](https://img.xkw.com/dksih/QBM/2016/11/29/1826268635201536/1826268636012544/STEM/c8fa5b04e30e48868fe132789b807597.png?resizew=16)
![](https://img.xkw.com/dksih/QBM/2016/11/29/1826268635201536/1826268636012544/STEM/3066e7be6d7c4c518443aac35ebc6fc5.png?resizew=16)
![](https://img.xkw.com/dksih/QBM/2016/11/29/1826268635201536/1826268636012544/STEM/b91007e2ea5e433e95db20f4365af044.png?resizew=16)
![](https://img.xkw.com/dksih/QBM/2016/11/29/1826268635201536/1826268636012544/STEM/97903bb1c17f421d99f9d22a60f06e1a.png?resizew=16)
![](https://img.xkw.com/dksih/QBM/2016/11/29/1826268635201536/1826268636012544/STEM/04d375abd23446d49614ae0320e80084.png?resizew=17)
![](https://img.xkw.com/dksih/QBM/2016/11/29/1826268635201536/1826268636012544/STEM/b5a2daa15b914c598c2eab346ad7223e.png?resizew=16)
![](https://img.xkw.com/dksih/QBM/2016/11/29/1826268635201536/1826268636012544/STEM/33f3cc1423584e0dbcb2758c3e25432d.png?resizew=17)
![](https://img.xkw.com/dksih/QBM/2016/11/29/1826268635201536/1826268636012544/STEM/0b593aab85fb4dbcb2ebdf05a19793da.png?resizew=17)
![](https://img.xkw.com/dksih/QBM/2016/11/29/1826268635201536/1826268636012544/STEM/855db6b1d0d84981842248c6e4474b0e.png?resizew=19)
![](https://img.xkw.com/dksih/QBM/2016/11/29/1826268635201536/1826268636012544/STEM/0dbdef66d115422081bc2e5a32f48d7c.png?resizew=12)
![](https://img.xkw.com/dksih/QBM/2016/11/29/1826268635201536/1826268636012544/STEM/847f57351bde4581abef8a8eca1c6630.png?resizew=72)
![](https://img.xkw.com/dksih/QBM/2016/11/29/1826268635201536/1826268636012544/STEM/c6b86275082f489cbaca3001edb878c6.png?resizew=74)
![](https://img.xkw.com/dksih/QBM/2016/11/29/1826268635201536/1826268636012544/STEM/cba340111acb4e49b35a90810589fa18.png?resizew=77)
![](https://img.xkw.com/dksih/QBM/2016/11/29/1826268635201536/1826268636012544/STEM/ae8730bc42424af6af4187c0829e1322.png?resizew=115)
![](https://img.xkw.com/dksih/QBM/2016/11/29/1826268635201536/1826268636012544/STEM/f1055c0362da4a4fbde3e599db2ebaeb.png?resizew=116)
![](https://img.xkw.com/dksih/QBM/2016/11/29/1826268635201536/1826268636012544/STEM/3ef175e21b1b4b148b88a747da214799.png?resizew=37)
![](https://img.xkw.com/dksih/QBM/2016/11/29/1826268635201536/1826268636012544/STEM/4f3b0d4465694c178a6a044b9be25f3a.png?resizew=42)
![](https://img.xkw.com/dksih/QBM/2016/11/15/1836136229879808/1826268636012544/STEM/2022ebbeb0664162b3f84a7ed49038ac.png?resizew=167)
求证:(1)
![](https://img.xkw.com/dksih/QBM/2016/11/29/1826268635201536/1826268636012544/STEM/3066e7be6d7c4c518443aac35ebc6fc5.png?resizew=16)
![](https://img.xkw.com/dksih/QBM/2016/11/29/1826268635201536/1826268636012544/STEM/b91007e2ea5e433e95db20f4365af044.png?resizew=16)
![](https://img.xkw.com/dksih/QBM/2016/11/29/1826268635201536/1826268636012544/STEM/97903bb1c17f421d99f9d22a60f06e1a.png?resizew=16)
![](https://img.xkw.com/dksih/QBM/2016/11/29/1826268635201536/1826268636012544/STEM/04d375abd23446d49614ae0320e80084.png?resizew=17)
![](https://img.xkw.com/dksih/QBM/2016/11/29/1826268635201536/1826268636012544/STEM/b5a2daa15b914c598c2eab346ad7223e.png?resizew=16)
![](https://img.xkw.com/dksih/QBM/2016/11/29/1826268635201536/1826268636012544/STEM/33f3cc1423584e0dbcb2758c3e25432d.png?resizew=17)
![](https://img.xkw.com/dksih/QBM/2016/11/29/1826268635201536/1826268636012544/STEM/0b593aab85fb4dbcb2ebdf05a19793da.png?resizew=17)
![](https://img.xkw.com/dksih/QBM/2016/11/29/1826268635201536/1826268636012544/STEM/855db6b1d0d84981842248c6e4474b0e.png?resizew=19)
(2)
![](https://img.xkw.com/dksih/QBM/2016/11/29/1826268635201536/1826268636012544/EXPLANATION/8fe0f5e54a904f04abfa0fdf835415be.png?resizew=68)
(3)
![](https://img.xkw.com/dksih/QBM/2016/11/29/1826268635201536/1826268636012544/STEM/26aac0e0723242a8984e34736049ce88.png?resizew=76)
您最近一年使用:0次