如图,在三棱锥
中,
,
,
分别为
的中点,
为线段
上一点.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/25/1dd4384e-5eeb-48f0-8d36-6113994a72e9.png?resizew=188)
(1)求直线
和
所成角的余弦值;
(2)当直线
平面
时,求四棱锥
的体积.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/891579e7c231584a8e16b8eeff79888e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/aecee82ab179207056c1e1f06e97af93.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/82db4fedaabaf9ded8584273d1a2be9c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ad056c25c0fdcbcc765eb5cbc6093f2b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/94c905599045694c50d401bfc78c394f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/895dc3dc3a6606ff487a4c4863e18509.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d40b319212a7e7528b053e1c7097e966.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/25/1dd4384e-5eeb-48f0-8d36-6113994a72e9.png?resizew=188)
(1)求直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/85c4bdfb0db1e31e8459df1d15f9ab55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6aa2b5e09f8ec785c59900a529390a02.png)
(2)当直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c372d059202ec388960b125d4a87dc84.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b46a7e819a5ed0b789f1f06bb0076422.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/efd01843371e9b744e639c1472325b26.png)
更新时间:2020-04-24 10:46:52
|
相似题推荐
解答题-问答题
|
适中
(0.65)
解题方法
【推荐1】在
中,角
所对的边分别为
.已知点
在直线
上.
(1)求角
的大小;(2)若
,求
面积的最大值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/24e0c10fb103930eabd5fa18e8f9bb06.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/76f0649064a085fb74c997fb507a9b6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/570c8e60ade774f91cf6bfe48a6117c6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e77da7418c213bad03d0f811e16c4778.png)
(1)求角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/036b23c94e305faaa1283996edc5b30c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
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解题方法
【推荐2】在
中,角A,B,C所对的边分别为a,b,c,面积为
,已知
.
(1)若
,求
;
(2)若
,
,求
的面积
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cf231f8f86fb922df4ca0c87f044cec3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/91adb92f13da1e519d457d821ba1c29d.png)
(1)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/953682eaa7294b153ff70cd5fb496e7e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c1311f32edf13f8caee5edb03f24a7ba.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fcdb7a488910743dc5c63afb394b87e2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ffe7a93172d308a58200e3c722fe1072.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cf231f8f86fb922df4ca0c87f044cec3.png)
您最近一年使用:0次
解答题-问答题
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适中
(0.65)
名校
解题方法
【推荐1】如图所示,在直三棱柱ABC-
,△ABC是边长为4的等边三角形,D、E、F分别为棱
、
、
的中点,点P在棱BC上,且![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e2b248fcdeca2711790a7a2ed2c6bff4.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/1/14/c8eda494-9350-4e9f-918a-1920e9379226.png?resizew=135)
(1)证明:AP∥平面DCE;
(2)求点B到平面APF的距离.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bf78d12ef45a9934eb207a43b1a5dee1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/56f7ba05c54b3de1f4378f7c8eb58328.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2777840758e70e7dbbc18cef8f3d6d2b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e0a851907ada2ac2c3c4880a6736d28a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e2b248fcdeca2711790a7a2ed2c6bff4.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/1/14/c8eda494-9350-4e9f-918a-1920e9379226.png?resizew=135)
(1)证明:AP∥平面DCE;
(2)求点B到平面APF的距离.
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解答题-问答题
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适中
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【推荐2】如图所示三棱锥,底面为等边
,
为
边中点,且
底面
,
.
![](https://img.xkw.com/dksih/QBM/2022/9/21/3071116689317888/3071241934667776/STEM/27ffc5dc8a0c449ebee3816065d28394.png?resizew=158)
(1)求三棱锥体积
;
(2)若
为
中点,求
与面
所成角的正切值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f3e126c16032892966489053f44b9048.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bef5239ddbb0972700ce01daf9ee7cf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/94dd33adfe9adf9641dcf93f728f2c24.png)
![](https://img.xkw.com/dksih/QBM/2022/9/21/3071116689317888/3071241934667776/STEM/27ffc5dc8a0c449ebee3816065d28394.png?resizew=158)
(1)求三棱锥体积
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cd689863203d6891a6a8ce8b40dd5a90.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/892909e49156f7dcc0650fcd65243877.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0628681907ac8d7fdb94d8bc1b15feb9.png)
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,在四棱锥
中,
平面
,
,
,且
,
,
.
![](https://img.xkw.com/dksih/QBM/2020/11/18/2595515576778752/2604783040479232/STEM/b83f271c7d8e4fcba1989ef27cc3eaab.png?resizew=219)
(1)求证:
;
(2)求直线
与
所成角的余弦值.
![](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/f571396be1aa4a8914a66f7d7abd6381.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cdb2dd10731b99c0f4f89ee957f8a239.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bab25af2ef12331d8b822c6f0a3844d3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0c1ac2e11788860424508ea9e80cf89d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0b80ee363635d73f601654339028daec.png)
![](https://img.xkw.com/dksih/QBM/2020/11/18/2595515576778752/2604783040479232/STEM/b83f271c7d8e4fcba1989ef27cc3eaab.png?resizew=219)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/746f70c9993f04a5037c53daf3d1af00.png)
(2)求直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e0629ce42392a7fe9be21d25c39c3e64.png)
您最近一年使用:0次
解答题-问答题
|
适中
(0.65)
解题方法
【推荐2】如图,直四棱柱
的底面是菱形,
,
,
分别是
的中点.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/15/c3a20079-2f3d-48cd-a3c7-92ca4c2c83a4.png?resizew=168)
(1)证明:
平面
;
(2)求异面直线
与
所成角的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6e09725691ee7851f54c0dee86b2bf55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e55a2310cbba5e050488cd9296eb195d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fcd0ced286a0fbc7e4862f8147264277.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f77e5821b24a76c71fdc2cf59fbba308.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2c7676b9fbff1a2f3c3087efc50fcd0e.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/15/c3a20079-2f3d-48cd-a3c7-92ca4c2c83a4.png?resizew=168)
(1)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/edcf19a7f0dd0cdf59516ae585025110.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fb5a463a03c549b0dba6d90e7f16a2af.png)
(2)求异面直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/10d8eb4a9f462ca0c1d49c3fe91e720d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e516121599c9fcc528121c00afcf52fc.png)
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