如图,在四棱锥P-ABCD中,底面四边形ABCD为梯形,AB∥CD,PA=CD=6,
,AD=2,AB⊥平面PAD.
![](https://img.xkw.com/dksih/QBM/2020/12/25/2621808214204416/2623366785851392/STEM/113150f54d3247ada1c6b68c6df64d9a.png?resizew=121)
(1)证明:PA⊥平面ABCD;
(2)若
,求二面角D-PC-B的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/19beca07629f567f1820ba4fbdeabb40.png)
![](https://img.xkw.com/dksih/QBM/2020/12/25/2621808214204416/2623366785851392/STEM/113150f54d3247ada1c6b68c6df64d9a.png?resizew=121)
(1)证明:PA⊥平面ABCD;
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/072bcb73fa16a1cb1378900123f3b9cd.png)
更新时间:2020-12-27 19:56:18
|
相似题推荐
解答题-证明题
|
适中
(0.65)
解题方法
【推荐1】在四棱锥中
,底面
是正方形,侧面
底面
,且
,分别为
的中点.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/9/5/dccbd6ec-bc60-4583-84f2-3aa9e3c43147.png?resizew=215)
(1)求证:
平面
;
(2)若
,求三棱锥
的体积.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0585b6c0f156eecf9662b9846d4eb693.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/93edc7bb513f40a89173121c8570cd65.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
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![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4528328ed320d6b5f29570c860593e5d.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/9/5/dccbd6ec-bc60-4583-84f2-3aa9e3c43147.png?resizew=215)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/06222ee533c2484ab25321a6abbf98cb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/852aabd89edffc1b94344ff3f1f31ccd.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fcd0ced286a0fbc7e4862f8147264277.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/16da61021211096a2ea933ba2f3632dd.png)
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解答题-证明题
|
适中
(0.65)
解题方法
【推荐2】如图,
为圆柱底面的内接四边形,
为底面圆的直径,
为圆柱的母线,且
.
;
(2)若
,点
在线段
上,且
,求四面体
的体积.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/48f3c9abbd78e9a6840ee5f30381daac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2e735a28578ba191da6d4f3b0f8e8729.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8e5ea309886e947ea7cb4b81716206fd.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a5aac151bc991b73bd7383ddf7ed468f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a0ed1ec316bc54c37c4286c208f55667.png)
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![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b49a94768192153f1b68caa5ae2173b8.png)
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您最近一年使用:0次
解答题-证明题
|
适中
(0.65)
名校
解题方法
【推荐1】如图,在底面是矩形的四棱锥
中,
平面
,
,
,
是PD的中点.
平面PAD;
(2)求平面EAC与平面ACD夹角的余弦值;
(3)求B点到平面EAC的距离.
![](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/f83a04565a8ebaa111894b724b0ba266.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e65a3e478bb87d094e3a0af30dd10ae8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/342d452a7b850cd3a15b23619ad39bd7.png)
(2)求平面EAC与平面ACD夹角的余弦值;
(3)求B点到平面EAC的距离.
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解答题-问答题
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适中
(0.65)
名校
【推荐2】如图,已知四棱台
的上、下底面分别是边长为2和4的正方形,平面
平面
,
,点
是棱
的中点,点
在棱
上.
点在什么位置时,使得
平面
;
(2)若面
与面
所成角的正弦值为
,求
的长.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6e09725691ee7851f54c0dee86b2bf55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0a45953045e613b97eeee15ac188ae2c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4b90595662af9a1936e1e703462cb69b.png)
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![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ab3e0dba5705e1d749cfb21ebbb2ed93.png)
(2)若面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e9edc50f7febbc2d5d8dcdc23a3630a7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b35708245a5da381178284f5ac7ce9c6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7e631a0a91c5c85bce742209159e5a63.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cb6ede9761b5b90f8dc137708e1ee90f.png)
您最近一年使用:0次
解答题-证明题
|
适中
(0.65)
【推荐3】如图,在矩形
中,
,
,
是
的中点,以
为折痕将
向上折起,使
为
,且平面
平面
.
![](https://img.xkw.com/dksih/QBM/2011/3/7/1570027970805760/1570027976278016/STEM/161b029c557643359939fdc37f8c437e.png?resizew=326)
(1)求证:
;
(2)求二面角
的大小.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fcd0ced286a0fbc7e4862f8147264277.png)
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![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d78abbad68bbbf12af10cd40ef4c353.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/68a83fdd2ba72a2dba0b6b10bb3e06b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63b43490ca09467a4c8cd8cfe91c94e4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e5b3bd5e6bc2a0a277d279bb01af9584.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/70fd4f68511d2393905617bfdeddddec.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/01ff27eea7545bb06f9472f91290c54e.png)
![](https://img.xkw.com/dksih/QBM/2011/3/7/1570027970805760/1570027976278016/STEM/161b029c557643359939fdc37f8c437e.png?resizew=326)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9e09a917d0d0d980d47bb3f399a010e1.png)
(2)求二面角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dbf1cd28324f085ea7386178d73fa232.png)
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