已知矩形
中,
,
分别在
上,且
,沿
将四边形
折成四边形
,使点
在平面
上的射影
在直线
上,且
.
![](https://img.xkw.com/dksih/QBM/2016/11/16/1573153395990528/1573153402322944/STEM/cc3b5b35dba74f71a36744bb5a6b190c.png)
(1)求证:
平面
;
(2)求
到平面
的距离.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/42a19e5964687db92aa9f346ab863ff3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ad056c25c0fdcbcc765eb5cbc6093f2b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6d93949d8a15aca4e79cedb978590571.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fc799080c04e01ce595151e11d957c96.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/49b50357a6545cae8348e3059312f520.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bedde879f99aed69d745d5ec8fe62084.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d8d205218becb6f101ac2a2409ba9b18.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/89e2a422324c123af2cf1d7553e17153.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b32c05247f6998d7a70d31d13be4148c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/73465a1f9aa03481295bf6bd3c6903ac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e6e490f703eb6c9bb1278c78ebc2d661.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f3f515c607a8cfbfc03b0e3718c1863c.png)
![](https://img.xkw.com/dksih/QBM/2016/11/16/1573153395990528/1573153402322944/STEM/cc3b5b35dba74f71a36744bb5a6b190c.png)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/561af6573f04eb7019025b5ee1e11a6c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/09c6b9b6dc6054d2e244051da08f7ea0.png)
(2)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/02d28b9fec2969b3313d4245cdc4c290.png)
更新时间:2016-12-05 00:51:42
|
【知识点】 平行公理
相似题推荐
解答题-证明题
|
适中
(0.64)
【推荐1】如图1,在直角梯形
中,
,
,
,
. 把
沿对角线
折起到
的位置,如图2所示,使得点
在平面
上的正投影
恰好落在线段
上,连接
,点
分别为线段
的中点.
![](https://img.xkw.com/dksih/QBM/2014/1/10/1571472845512704/1571472850911232/STEM/8703f1c61cd041c8b5350497a90f0a1e.png)
(1)求证:平面
平面
;
(2)求直线
与平面
所成角的正弦值;
(3)在棱
上是否存在一点
,使得
到点
四点的距离相等?请说明理由.
![](https://img.xkw.com/dksih/QBM/2014/1/10/1571472845512704/1571472850911232/STEM/acbfee6c40f04daf9a422c0df8122eca.png)
![](https://img.xkw.com/dksih/QBM/2014/1/10/1571472845512704/1571472850911232/STEM/d737ba4c9fb1483eac8ddf1afc576ce4.png)
![](https://img.xkw.com/dksih/QBM/2014/1/10/1571472845512704/1571472850911232/STEM/0c2b5d83a5964a759997cf6a715da794.png)
![](https://img.xkw.com/dksih/QBM/2014/1/10/1571472845512704/1571472850911232/STEM/799983c3c51e4511999cf8549d3ffd0e.png)
![](https://img.xkw.com/dksih/QBM/2014/1/10/1571472845512704/1571472850911232/STEM/a1e2a4aa0e3a4cc590044c3632d9aa57.png)
![](https://img.xkw.com/dksih/QBM/2014/1/10/1571472845512704/1571472850911232/STEM/643569284bd64d64966623a31d56ced1.png)
![](https://img.xkw.com/dksih/QBM/2014/1/10/1571472845512704/1571472850911232/STEM/ec455069006a45028844549f0fcd64b2.png)
![](https://img.xkw.com/dksih/QBM/2014/1/10/1571472845512704/1571472850911232/STEM/09bff9032f2347f39639acac903b2339.png)
![](https://img.xkw.com/dksih/QBM/2014/1/10/1571472845512704/1571472850911232/STEM/f7584886dbd74f73893d867483773b47.png)
![](https://img.xkw.com/dksih/QBM/2014/1/10/1571472845512704/1571472850911232/STEM/6d3a6522536947ee99a1139538b7798e.png)
![](https://img.xkw.com/dksih/QBM/2014/1/10/1571472845512704/1571472850911232/STEM/f0e78868ac7c41a4b859df22e93c4f40.png)
![](https://img.xkw.com/dksih/QBM/2014/1/10/1571472845512704/1571472850911232/STEM/ec455069006a45028844549f0fcd64b2.png)
![](https://img.xkw.com/dksih/QBM/2014/1/10/1571472845512704/1571472850911232/STEM/af8a61a25da14c1d8fca95dea6895514.png)
![](https://img.xkw.com/dksih/QBM/2014/1/10/1571472845512704/1571472850911232/STEM/83efd06448e14ad2b198a62230d3e481.png)
![](https://img.xkw.com/dksih/QBM/2014/1/10/1571472845512704/1571472850911232/STEM/9e52e53108a84129a5db459992b2fb56.png)
![](https://img.xkw.com/dksih/QBM/2014/1/10/1571472845512704/1571472850911232/STEM/8703f1c61cd041c8b5350497a90f0a1e.png)
(1)求证:平面
![](https://img.xkw.com/dksih/QBM/2014/1/10/1571472845512704/1571472850911232/STEM/65bca19ba6234125a9902a224ac9294a.png)
![](https://img.xkw.com/dksih/QBM/2014/1/10/1571472845512704/1571472850911232/STEM/1982844570864da1a7383ddb2e491c85.png)
(2)求直线
![](https://img.xkw.com/dksih/QBM/2014/1/10/1571472845512704/1571472850911232/STEM/fb297f663881439da78576a4a89f9d0c.png)
![](https://img.xkw.com/dksih/QBM/2014/1/10/1571472845512704/1571472850911232/STEM/5b8e12b42d6b4a8fab7737b493d8ffda.png)
(3)在棱
![](https://img.xkw.com/dksih/QBM/2014/1/10/1571472845512704/1571472850911232/STEM/78e4f64fdb3a40ff8e11d11914170911.png)
![](https://img.xkw.com/dksih/QBM/2014/1/10/1571472845512704/1571472850911232/STEM/83b6f81eb34f4c979d0204bb86915085.png)
![](https://img.xkw.com/dksih/QBM/2014/1/10/1571472845512704/1571472850911232/STEM/83b6f81eb34f4c979d0204bb86915085.png)
![](https://img.xkw.com/dksih/QBM/2014/1/10/1571472845512704/1571472850911232/STEM/3e3511228cc149688ee089b1eceba64f.png)
您最近一年使用:0次
解答题-证明题
|
适中
(0.64)
【推荐2】如图,已知四棱锥
的底面
是平行四边形,
平面
,
是
的中点,
是
的中点.
![](https://img.xkw.com/dksih/QBM/2016/7/5/1572890305806336/1572890311671808/STEM/1c95f91257bc43529dd50282eab6b46b.png)
(1)求证:
平面
;
(2)若平面
平面
,求证:
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/56fbe4053a65b67949981f24c0d30b6b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/34b0c4c783dd55685bd3e88bb31c6696.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dc9b6976a079eb695ea89736a6481479.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/34b0c4c783dd55685bd3e88bb31c6696.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8f9c827e46d1a395fafbf15cdd6c6c42.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b693717f525facc79b9a500ed998b109.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9f92c0005348ac35069a9fd56068da81.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/435f34602291e9e293ff64a1606e29dc.png)
![](https://img.xkw.com/dksih/QBM/2016/7/5/1572890305806336/1572890311671808/STEM/1c95f91257bc43529dd50282eab6b46b.png)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4db17202e39865fc3d37c2b2c7196de1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0c54157dc38fe4de0d9c8b72fe9b4116.png)
(2)若平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/945bfb45071bc1019b5820dd42c8123b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/baf5cb457a768676c10da10ccfdbb2fe.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a0e669a3e5b671de93a1ba5a335e5528.png)
您最近一年使用:0次