名校
1 . 如图所示,已知长方体
中,
,
为
的中点,将
沿
折起,使得
.
![](https://img.xkw.com/dksih/QBM/2017/3/31/1655498603372544/1655671527243776/STEM/eedf1d77f8c146b3be95190bb8c18d65.png?resizew=531)
(1)求证:平面
平面
;
(2)是否存在满足
的点
,使得二面角
为大小为
?若存在,求出相应的实数
;若不存在,请说明理由.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/100af11e6cb83b56437f2db7dadeb9f4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9e52a8f07834cbbbe4224962672fbbb2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4e1e88b36ff71fe69c07bade0f95f1ef.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d50703c46b6153945d718b198f03b4b5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/804c0e2a375b5f4ff1c420532968efc3.png)
![](https://img.xkw.com/dksih/QBM/2017/3/31/1655498603372544/1655671527243776/STEM/eedf1d77f8c146b3be95190bb8c18d65.png?resizew=531)
(1)求证:平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0bb5012f6c70a1e98d682b6d021fadd8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0760712e3e2ea02b755b751e760d0c55.png)
(2)是否存在满足
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/eaac8d2b8d350312c425b4f0dc5b8cd8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a5266895d3c1fcb350a745bc779433b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/af9955b5aebb73cd84447e8541f901ac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/36a1b09c653185842513e24ebba60bb3.png)
您最近一年使用:0次
2017-03-31更新
|
1377次组卷
|
4卷引用:河南省息县第一高级中学2017届高三下学期第二次阶段测试理数试题
12-13高二上·浙江温州·期末
2 . 如图,在平行六面体
中,
,
,
,
(1)求
;
(2)求证:
平面
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6e09725691ee7851f54c0dee86b2bf55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cead0e8eadfdcefa334953e88864f424.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e6906f59d09ce31956d6f5ea2b23fc77.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7362be3007eef9e6cdcbdbdad769eab7.png)
(1)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b448365344987329313d7489c756d738.png)
(2)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5a5928c98b341b16d4b5a5b931d2929d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2d9a8181f7a7fe7f3fac872ce9534f15.png)
![](https://img.xkw.com/dksih/QBM/2012/2/20/1570755401695232/1570755406807040/STEM/7086ca2ef0864288a92edfb40ba20846.png?resizew=324)
您最近一年使用:0次