12-13高二上·广东梅州·期末
1 . 如图正方体ABCD-
中,E、F、G分别是
、AB、BC的中点.
(1)证明:
⊥平面AEG;
(2)求
,![](https://img.xkw.com/dksih/QBM/2012/2/15/1570739834798080/1570739840245760/STEM/361ecb64299d4e038ee9985b012b7140.png?resizew=45)
![](https://img.xkw.com/dksih/QBM/2012/2/15/1570739834798080/1570739840245760/STEM/289a500d10474c9cb90e1f9405415070.png?resizew=62)
![](https://img.xkw.com/dksih/QBM/2012/2/15/1570739834798080/1570739840245760/STEM/dda4d0cee1974a3998bece70cd3586a1.png?resizew=29)
(1)证明:
![](https://img.xkw.com/dksih/QBM/2012/2/15/1570739834798080/1570739840245760/STEM/0ff6e007c8664ee097974085ee16481e.png?resizew=32)
(2)求
![](https://img.xkw.com/dksih/QBM/2012/2/15/1570739834798080/1570739840245760/STEM/1b65aa56036a434bb9100479b88dd19d.png?resizew=65)
![](https://img.xkw.com/dksih/QBM/2012/2/15/1570739834798080/1570739840245760/STEM/361ecb64299d4e038ee9985b012b7140.png?resizew=45)
![](https://img.xkw.com/dksih/QBM/2012/2/15/1570739834798080/1570739840245760/STEM/c44a38897617417690cee742c5d653c5.png?resizew=124)
您最近一年使用:0次
2 . 如图,
是半径为
的半圆,
为直径,点
为
的中点,点
和点
为线段
的三等分点,平面
外一点
满足
平面
,
.
![](https://img.xkw.com/dksih/QBM/2015/7/10/1572178491924480/1572178497880064/STEM/04632768d1524054a33db6076799e2ca.png)
(1)证明:
;
(2)求点
到平面
的距离.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/46e2da608b66c9aee03e2503388ba4fd.png)
![](https://img.xkw.com/dksih/QBM/2015/7/10/1572178491924480/1572178497880064/STEM/3fb4308cc4024daea54217935a902f43.png)
![](https://img.xkw.com/dksih/QBM/2015/7/10/1572178491924480/1572178497880064/STEM/5ca566db478945e397a19f3ff6a67e8b.png)
![](https://img.xkw.com/dksih/QBM/2015/7/10/1572178491924480/1572178497880064/STEM/fe80ee3aa02c4773bb790f6980a9cef0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://img.xkw.com/dksih/QBM/2015/7/10/1572178491924480/1572178497880064/STEM/030b4dcd10654a07b400fab2bcdfb45a.png)
![](https://img.xkw.com/dksih/QBM/2015/7/10/1572178491924480/1572178497880064/STEM/a8cfdf7ab62b4a02bbc36353f7be767c.png)
![](https://img.xkw.com/dksih/QBM/2015/7/10/1572178491924480/1572178497880064/STEM/3546f7c57fc64148b5e6f45eadeba0b4.png)
![](https://img.xkw.com/dksih/QBM/2015/7/10/1572178491924480/1572178497880064/STEM/6868bd0380a44a74aa371b219af30ef0.png)
![](https://img.xkw.com/dksih/QBM/2015/7/10/1572178491924480/1572178497880064/STEM/94a7b841abac4a5b9068f80ec5153899.png)
![](https://img.xkw.com/dksih/QBM/2015/7/10/1572178491924480/1572178497880064/STEM/d0d033e0948343ce926a7f075e514bdd.png)
![](https://img.xkw.com/dksih/QBM/2015/7/10/1572178491924480/1572178497880064/STEM/e5939a524876480f8d81b59a7d218146.png)
![](https://img.xkw.com/dksih/QBM/2015/7/10/1572178491924480/1572178497880064/STEM/ed509aa771b94ef1b9dfcd696159673d.png)
![](https://img.xkw.com/dksih/QBM/2015/7/10/1572178491924480/1572178497880064/STEM/04632768d1524054a33db6076799e2ca.png)
(1)证明:
![](https://img.xkw.com/dksih/QBM/2015/7/10/1572178491924480/1572178497880064/STEM/70db6c961a75483d938cede2927c8e52.png)
(2)求点
![](https://img.xkw.com/dksih/QBM/2015/7/10/1572178491924480/1572178497880064/STEM/030b4dcd10654a07b400fab2bcdfb45a.png)
![](https://img.xkw.com/dksih/QBM/2015/7/10/1572178491924480/1572178497880064/STEM/16b8c3810d5b40f69a346421914b90c0.png)
您最近一年使用:0次
3 . 如图,在三棱锥
中,平面
平面
,
,
,过
作
,垂足为
,点
分别是棱
的中点.
![](https://img.xkw.com/dksih/QBM/2015/7/10/1572177749975040/1572177755856896/STEM/5e6ed79619724f8a995e4e288d71fa05.png)
求证:(1)平面
平面
; (2)
.
![](https://img.xkw.com/dksih/QBM/2015/7/10/1572177749975040/1572177755856896/STEM/b8b4627e0ee746b6a869b7c0518e7c50.png)
![](https://img.xkw.com/dksih/QBM/2015/7/10/1572177749975040/1572177755856896/STEM/4dde54b789a045e299bd3d347b0f33fe.png)
![](https://img.xkw.com/dksih/QBM/2015/7/10/1572177749975040/1572177755856896/STEM/a0abd3dff20f4df78d34d33ccc3958be.png)
![](https://img.xkw.com/dksih/QBM/2015/7/10/1572177749975040/1572177755856896/STEM/668354606a1b42a7a43170ced66bdb70.png)
![](https://img.xkw.com/dksih/QBM/2015/7/10/1572177749975040/1572177755856896/STEM/c57030df5014430e8803442c1585e31e.png)
![](https://img.xkw.com/dksih/QBM/2015/7/10/1572177749975040/1572177755856896/STEM/7733030cd3bd415c9ea3908b2140e5ac.png)
![](https://img.xkw.com/dksih/QBM/2015/7/10/1572177749975040/1572177755856896/STEM/12222ea1107d4aaca273fc766d954b7d.png)
![](https://img.xkw.com/dksih/QBM/2015/7/10/1572177749975040/1572177755856896/STEM/dd4c6c9bac7d4143a2f65e19893451c5.png)
![](https://img.xkw.com/dksih/QBM/2015/7/10/1572177749975040/1572177755856896/STEM/2288524aa5c04a7192c6e88318aef7dc.png)
![](https://img.xkw.com/dksih/QBM/2015/7/10/1572177749975040/1572177755856896/STEM/fababe80039d4339ba0094fc6b0e886d.png)
![](https://img.xkw.com/dksih/QBM/2015/7/10/1572177749975040/1572177755856896/STEM/5e6ed79619724f8a995e4e288d71fa05.png)
求证:(1)平面
![](https://img.xkw.com/dksih/QBM/2015/7/10/1572177749975040/1572177755856896/STEM/8a9bad60b51d4a6393ed4a923b102964.png)
![](https://img.xkw.com/dksih/QBM/2015/7/10/1572177749975040/1572177755856896/STEM/4ec3160b173a486f849f9707554229a5.png)
![](https://img.xkw.com/dksih/QBM/2015/7/10/1572177749975040/1572177755856896/STEM/db54de8cdaf74f62a6c9b6da522746b5.png)
您最近一年使用:0次