如图,在三棱锥
中,
平面
,
,
,
![](https://img.xkw.com/dksih/QBM/2015/7/16/1572185250734080/1572185256706048/STEM/41fe1843ad2246cb86ae9dfbcf6956f6.png?resizew=286)
(Ⅰ)平面
平面
;
(Ⅱ)
为
的延长线上的一点.若二面角
的大小为
,求
的长.
![](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/e7b7c83470489253394bd288d7c920df.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6d577e4445c9429b9090dcfe08ff3eb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b3a6421b036f09167a98d3f484b3d211.png)
![](https://img.xkw.com/dksih/QBM/2015/7/16/1572185250734080/1572185256706048/STEM/41fe1843ad2246cb86ae9dfbcf6956f6.png?resizew=286)
(Ⅰ)平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e4aa9084b8fe0fe05c4388d1f835587b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bef5239ddbb0972700ce01daf9ee7cf.png)
(Ⅱ)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7dea2ae9d515f9ab351ad72306b776ee.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/df6aaed07f0b69eee41de11613fc74de.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f6b86c22b670a8e9f3896f9e8883fbbb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/85c4bdfb0db1e31e8459df1d15f9ab55.png)
更新时间:2016-12-03 16:02:00
|
相似题推荐
解答题-问答题
|
较难
(0.4)
名校
【推荐1】如图,正方形
与梯形
所在的平面互相垂直,
,
,
,
,
为
的中点.
(1)求证:
平面
;
(2)求证:平面
平面
;
(3)求平面
与平面
所成锐二面角的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3ecc1cb55a57dde481f8dd07ab150676.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cdb2dd10731b99c0f4f89ee957f8a239.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b37591109b0a0ec5ffe2133f83310eca.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/27db558e8db4c957654c8e5cecd2d2dc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e673ef2d48215ca84a48377f17d6df00.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4eedae8d316c76e3d0b451256de03fb9.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/9/30/27396d36-39a5-417e-a0a1-bbd7128408ec.png?resizew=192)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2061b9ab3862d9c36d32c4ffef91145a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3ecc1cb55a57dde481f8dd07ab150676.png)
(2)求证:平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3547a914468b082d8d8741b974a03190.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e9a814b70236a108be5d6e7ff271fe92.png)
(3)求平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e9a814b70236a108be5d6e7ff271fe92.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3ecc1cb55a57dde481f8dd07ab150676.png)
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解答题-证明题
|
较难
(0.4)
解题方法
【推荐2】如图1,C,D是以AB为直径的圆上两点,且
,
,将
所在的半圆沿直径AB折起,使得点C在平面ABD上的射影E在BD上,如图2.
![](https://img.xkw.com/dksih/QBM/2020/7/19/2509149605011456/2509803206803456/STEM/7157a5992725421dabd07bcf6d8bf8da.png?resizew=364)
(1)求证:平面
平面BCD;
(2)在线段AB上是否存在点F,使得
平面CEF?若存在,求出
的值;若不存在,请说明理由.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4c4e4a162f12d12a082b8d8fdd1aeab9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4b10134e7a46e6f6f7cb9d5e2371727d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://img.xkw.com/dksih/QBM/2020/7/19/2509149605011456/2509803206803456/STEM/7157a5992725421dabd07bcf6d8bf8da.png?resizew=364)
(1)求证:平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/17580410bf63dba4fe164265afaac4cc.png)
(2)在线段AB上是否存在点F,使得
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/810ee7bc82b6f452afb3fc18691abc3b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8ddb339df743a4f0347823beee5516b6.png)
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解答题-问答题
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较难
(0.4)
名校
解题方法
【推荐1】如图四棱锥
在以
为直径的圆上,
平面
为
的中点,
,证明:
⊥
;
(2)当二面角
的正切值为
时,求点
到平面
距离的最大值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9abf66efc0b676cecb31e811c6a32105.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/10c83f8945042b9c8fb2fbdac9308d62.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5d30742fc73d4086a57419e2614860d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2c2bc5e50b8dfa02601c70822252854a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/853b60fafb31cab8f1bec5510bf1c984.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e6e490f703eb6c9bb1278c78ebc2d661.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
(2)当二面角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/822afb8100552bb2f12c7dde188ae388.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/35361e76a7c85d1886728c8d0200b234.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9ef796b46e68fe77b117ff0483d2370c.png)
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解答题-证明题
|
较难
(0.4)
名校
解题方法
【推荐2】如图在四面体
中,
是边长为2的等边三角形,
为直角三角形,其中D为直角顶点,
.E、F、G、H分别是线段
、
、
、
上的动点,且四边形
为平行四边形.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/8/14/4b5bf256-c2cb-4351-a191-2431744eb9f0.png?resizew=182)
(1)求证:![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
平面
;
(2)设二面角
的平面角为
,求
在区间
变化的过程中,线段
在平面
上的投影所扫过的平面区域的面积;
(3)设
,且平面
平面
,则当
为何值时,多面体
的体积恰好为
?
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0005e1ef60f6ddc5f9a83e3de1ef3b2e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9a03e0d9ec888c1c343853295c40318b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d78abbad68bbbf12af10cd40ef4c353.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7d97dc3b752832906de41447bb58a341.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/611f100dcfa7803db6eb233e2e7f2dab.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/8/14/4b5bf256-c2cb-4351-a191-2431744eb9f0.png?resizew=182)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fb31ef428bd9de9bc875b343feded3c7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/611f100dcfa7803db6eb233e2e7f2dab.png)
(2)设二面角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5ec2524be492bca0d1566bf848066f10.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c24095e409b025db711f14be783a406c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c24095e409b025db711f14be783a406c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/18c9aeed3c8c5a04e48d011c607f9142.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/67d822262ff00915910e5b87d81ad1ba.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ca67a5b8f69507c8b80379e86f90a8ce.png)
(3)设
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/02970ebdd2b0f1a9c25d0e237865fb14.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a3d7090639341730951c1bc3c9b6164e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ca67a5b8f69507c8b80379e86f90a8ce.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/df64046e91b047037f19e4032e3b6de3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3edbdc69d35ac048be3be891555738e2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/56d266a04f3dc7483eddbc26c5e487db.png)
您最近一年使用:0次
【推荐3】如图,在正四棱锥P-ABCD中,AB=2,侧面PAD与底面ABCD的夹角为
.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/9/8a02af48-def4-4760-b75e-60b2c33ed9c6.png?resizew=190)
(1)求正四棱锥P-ABCD的体积;
(2)若点M是正四棱锥P-ABCD内任意一点,点M到平面ABCD,平面PAB,平面PBC,平面PCD,平面PDA的距离分别为
,
,
,
,
,证明:
;
(3)若球O是正四棱锥P-ABCD的内切球,点Q是正方形ABCD内一动点,且OQ=OP,当点Q沿着它所在的轨迹运动一周时,求线段OQ所形成的曲面与底面ABCD所围成的几何体的表面积.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac1a63ab608517bb10aa036783dfb51f.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/9/8a02af48-def4-4760-b75e-60b2c33ed9c6.png?resizew=190)
(1)求正四棱锥P-ABCD的体积;
(2)若点M是正四棱锥P-ABCD内任意一点,点M到平面ABCD,平面PAB,平面PBC,平面PCD,平面PDA的距离分别为
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5edf900c810371fb21297c15f86d8743.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b31ac1def558351e2e3ed1235c570530.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/342d0252c1b2f7d2a84b5c985d19d547.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8d31659f106fba3c9750661eb0e3c3eb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b89869be2ca7faeac74926049fa509b0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/06420e9f8ba6e63d76395141986f60ed.png)
(3)若球O是正四棱锥P-ABCD的内切球,点Q是正方形ABCD内一动点,且OQ=OP,当点Q沿着它所在的轨迹运动一周时,求线段OQ所形成的曲面与底面ABCD所围成的几何体的表面积.
您最近一年使用:0次