如图,在三棱锥
中,平面
平面
,
是等边三角形,
,且
,
、
分别是
,
的中点.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/10/31/6a70b8f3-4282-4568-b453-dc8911aedc92.png?resizew=170)
(1)求证:
平面
;
(2)求三棱锥
的体积.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63397cda22cb1fad59cf966dfb588643.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e4aa9084b8fe0fe05c4388d1f835587b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bef5239ddbb0972700ce01daf9ee7cf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2205cffebf8c4d5f81d15ed7b85c8936.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/615fc8790237a1b09af51d6bcad6b595.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/209acf15985d1ea1ad86fc4a37e38c0b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d2be49c37e30a3ced0364c3e74d8c687.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/10/31/6a70b8f3-4282-4568-b453-dc8911aedc92.png?resizew=170)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/373f735f0f04d11f1951eaef1bb78b6a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6bf126cfed85fa9b7720ec6f7b0008dc.png)
(2)求三棱锥
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63397cda22cb1fad59cf966dfb588643.png)
更新时间:2021-02-02 21:11:23
|
相似题推荐
解答题-问答题
|
较易
(0.85)
名校
解题方法
【推荐1】鳖臑是我国古代对四个面均为直角三角形的三棱锥的称呼.如图,三棱锥
是一鳖臑,其中
,
,
,
,且高
,
.
![](https://img.xkw.com/dksih/QBM/2022/4/21/2963077774426112/2964882593931264/STEM/cf2ffd26-da6d-41e6-93b8-e935f5b3de01.png?resizew=144)
(1)求三棱锥
的体积和表面积;
(2)求三棱锥
外接球体积和内切球的半径.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/891579e7c231584a8e16b8eeff79888e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/080db3af81b29ed10144a1c2e2a4fb8a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8915e8e775538d41debf1933102c6b86.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4bd6a2b112facda441f4e34bf5c145fa.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3bf10d92f20501e19d25f6f4159aab89.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e6834ac70927ae08d7d36a1922403c9e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/24f0459ed3af308dfbdaa5314d8ef327.png)
![](https://img.xkw.com/dksih/QBM/2022/4/21/2963077774426112/2964882593931264/STEM/cf2ffd26-da6d-41e6-93b8-e935f5b3de01.png?resizew=144)
(1)求三棱锥
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/891579e7c231584a8e16b8eeff79888e.png)
(2)求三棱锥
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/891579e7c231584a8e16b8eeff79888e.png)
您最近一年使用:0次
【推荐2】在四棱锥Q-ABCD中,底面ABCD是正方形,若
,
,
.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/4/10/e87c7abe-6fde-4b36-8a0b-b7bfebd50666.png?resizew=180)
(1)证明:平面
⊥平面
;
(2)求四棱锥
的体积与表面积.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/09d27bd71d79cb19eb554175e4ef0867.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6a3d0f667ef7ca851f514f2e742a8624.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a8a512bcb83a2e952d2f1f877f1ceaa5.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/4/10/e87c7abe-6fde-4b36-8a0b-b7bfebd50666.png?resizew=180)
(1)证明:平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e40cae1138ce408cf7ebbe14f152d6e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
(2)求四棱锥
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/55c6caa0455442437177ab9b995df37b.png)
您最近一年使用:0次
解答题-证明题
|
较易
(0.85)
【推荐1】直三棱柱
中,
是
的中点,
与
交于点
,
在线段
上,且
,
,
,
,
.
(1)求证:
平面
;
(2)求直线
与平面
所成的角的正弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/42d3a82b8e587ee890467835bc4e854c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/10d8eb4a9f462ca0c1d49c3fe91e720d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/24bb49fdc6b6bbb2449fdf8a0de769d3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a0ed1ec316bc54c37c4286c208f55667.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/24bb49fdc6b6bbb2449fdf8a0de769d3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2f5929eb2464219b12f43a1ff0fe9fa7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ad1a56baf43ffdf67bc8460856e31fec.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fcd0ced286a0fbc7e4862f8147264277.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ca036d049f5205cf04cb1b9c5cd03f97.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a7502eee6f33e8c940dec63ab6473c52.png)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7790296627fb9a73486e5ce271643a71.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7935fe3125f247b7bea4f065ce9ad985.png)
(2)求直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7935fe3125f247b7bea4f065ce9ad985.png)
![](https://img.xkw.com/dksih/QBM/2017/7/19/1733353730637824/1734405477982208/STEM/40d2b115d8304549ab77eb1d30367c56.png?resizew=252)
您最近一年使用:0次
解答题-证明题
|
较易
(0.85)
名校
【推荐2】如图,在四棱锥
中,平面
平面
,
,且
,
.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/1/5/1b6bc531-fca5-4828-ba2c-61444540bb16.png?resizew=132)
(Ⅰ)求证:
;
(Ⅱ)若
为
的中点,求证:
平面
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0585b6c0f156eecf9662b9846d4eb693.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e4aa9084b8fe0fe05c4388d1f835587b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0facf189b2a3153beb7b9e077d3b1146.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4d34ac97b116fc5c4e99d07dda1c50b3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/45acdbac251ca6b76a166c1242e71df9.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/1/5/1b6bc531-fca5-4828-ba2c-61444540bb16.png?resizew=132)
(Ⅰ)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8a15a004f7d47ed595f063e60075223a.png)
(Ⅱ)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d2be49c37e30a3ced0364c3e74d8c687.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d2a955954cd1b57f194bb8f199f66cdc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/80f747eb5b2d21c9de962cbfd4ec4bb7.png)
您最近一年使用:0次
解答题-证明题
|
较易
(0.85)
名校
解题方法
【推荐1】如图,在三棱锥
中,点
、
分别是
、
的中点,
是锐角三角形.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/14/c6b5d5dd-75d4-494c-8a41-7d861257b997.png?resizew=177)
(1)求证;
平面
;
(2)若平面
平面
,
,求证;
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63397cda22cb1fad59cf966dfb588643.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a0ed1ec316bc54c37c4286c208f55667.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/48f3c9abbd78e9a6840ee5f30381daac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1e582d73b96ba649378379c3074d506d.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/14/c6b5d5dd-75d4-494c-8a41-7d861257b997.png?resizew=177)
(1)求证;
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f8c2b786c64e6a9ed2ec5670cde74f86.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/87c0bfeadcf17b2a45896071f07a4a5a.png)
(2)若平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e4aa9084b8fe0fe05c4388d1f835587b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bef5239ddbb0972700ce01daf9ee7cf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f0063f3f48e49f2970ec7f097567cef5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d60964e720188e325eb18c9528b1fa95.png)
您最近一年使用:0次
解答题-证明题
|
较易
(0.85)
解题方法
【推荐2】如图,在四棱锥P-ABCD中,底面ABCD是直角梯形,且AD∥BC,AB⊥BC,BC=2AD,已知平面PAB⊥平面ABCD,E,F分别为BC,PC的中点.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/13/c752dd6b-d635-4f34-8a55-144a142d71d0.png?resizew=131)
求证:(1)AB
平面DEF ;
(2)BC⊥平面DEF .
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/13/c752dd6b-d635-4f34-8a55-144a142d71d0.png?resizew=131)
求证:(1)AB
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/895d6f710d5f67e1d4c7408d50d77281.png)
(2)BC⊥平面DEF .
您最近一年使用:0次