名校
1 . 在四棱锥
中,
底面
,
,
,
,点
在棱
上,且满足
.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/15/1168cf46-7b5f-4865-94e8-cf0d0e0924b7.png?resizew=175)
(1)证明:
平面
;
(2)若
,求二面角
的余弦值.
![](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/1134c8e3440abb6cd385af2c169037fe.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f571396be1aa4a8914a66f7d7abd6381.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4575a365b8e619654a7327d216f23783.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e0629ce42392a7fe9be21d25c39c3e64.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/575c840debd9149001fe32fd9d2b5c03.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/15/1168cf46-7b5f-4865-94e8-cf0d0e0924b7.png?resizew=175)
(1)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/11d27ff0b39832f094ec51e28721d739.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1e582d73b96ba649378379c3074d506d.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/af0788c2784a2c5bb9f47ffef6902f18.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7a17158a669a634e3db538ce76471950.png)
您最近一年使用:0次
解题方法
2 . 如图,在四棱锥
中,底面
为直角梯形,
,
,
平面
,
,设点M为
的中点.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/18/93a9146d-8dea-49b8-99d7-c8d2124b3ecc.jpg?resizew=189)
(1)若四棱锥
的体积为2,求异面直线
,
所成角的余弦值;
(2)若二面角
的余弦值为
,求
的长.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/faeb97acf19bd3b2c6c77c2814df4d2f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f571396be1aa4a8914a66f7d7abd6381.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9060f03b9ee41d70d135b1e1a8902ce9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/10c83f8945042b9c8fb2fbdac9308d62.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/87d11dd7422f4703763abc23d83c7584.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2c2bc5e50b8dfa02601c70822252854a.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/18/93a9146d-8dea-49b8-99d7-c8d2124b3ecc.jpg?resizew=189)
(1)若四棱锥
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/faeb97acf19bd3b2c6c77c2814df4d2f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d50703c46b6153945d718b198f03b4b5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d78abbad68bbbf12af10cd40ef4c353.png)
(2)若二面角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3c123937cd5c0769090771598d6aee7c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e08e91d2fa9519a5f48d488176700499.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
您最近一年使用:0次
2021-01-28更新
|
94次组卷
|
2卷引用:河南省三门峡市2020-2021学年高二上学期期末数学(理科)试题
解题方法
3 . 如图,在四棱锥
中,底面
为直角梯形,
,
,
平面
,
,
.
![](https://img.xkw.com/dksih/QBM/2021/1/23/2642465470758912/2645988240670720/STEM/8e20c89c-fb3b-482a-bc8c-7b2f5429671b.png?resizew=247)
(1)设点
为
的中点,求异面直线
、
所成角的余弦值;
(2)求二面角
的大小.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/faeb97acf19bd3b2c6c77c2814df4d2f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f571396be1aa4a8914a66f7d7abd6381.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9060f03b9ee41d70d135b1e1a8902ce9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/10c83f8945042b9c8fb2fbdac9308d62.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/87d11dd7422f4703763abc23d83c7584.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3f4aca5534bce25acaeb7379deed8f8f.png)
![](https://img.xkw.com/dksih/QBM/2021/1/23/2642465470758912/2645988240670720/STEM/8e20c89c-fb3b-482a-bc8c-7b2f5429671b.png?resizew=247)
(1)设点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2c2bc5e50b8dfa02601c70822252854a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d50703c46b6153945d718b198f03b4b5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d78abbad68bbbf12af10cd40ef4c353.png)
(2)求二面角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4157481699496e311bb990a1f3310476.png)
您最近一年使用:0次
2021-01-28更新
|
110次组卷
|
2卷引用:河南省三门峡市2020-2021学年高二上学期期末数学(理科)试题
解题方法
4 . 如图,在三棱锥
中,
平面
,
为等腰直角三角形,
,点
在
上,且
,则
与平面
所成角的正弦值为_________ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63397cda22cb1fad59cf966dfb588643.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ccd4fd4b7a4d6b8ca0c5827c055a9ce7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bef5239ddbb0972700ce01daf9ee7cf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/90b40c2b0ab8e1cfe5112d428b4b829f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a9082547ec262e00ece8072817097d4e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/48f3c9abbd78e9a6840ee5f30381daac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9b60fb524f924fb66b26a1f2577d9935.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d2be49c37e30a3ced0364c3e74d8c687.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7abd284f76d9f5769bc189508ce2572b.png)
![](https://img.xkw.com/dksih/QBM/2021/1/23/2642465470758912/2645988240465920/STEM/c3085c1e47c54651b7d9e2f366394b2e.png?resizew=172)
您最近一年使用:0次
2021-01-28更新
|
164次组卷
|
3卷引用:河南省三门峡市2020-2021学年高二上学期期末数学(理科)试题