如图,斜三棱柱
中,点
在底面
上的射影恰好是
的中点,且
.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/28/6ff40ad4-601b-4e62-802a-f81316452aac.png?resizew=180)
(1)证明:平面
平面
;
(2)求直线
与平面
所成角的正弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/986ba572d8373df48c996f8c8611498c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bef5239ddbb0972700ce01daf9ee7cf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f3322f9ae597c87dbf20ea781efc0991.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/28/6ff40ad4-601b-4e62-802a-f81316452aac.png?resizew=180)
(1)证明:平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ed0ad6e27ea2d5d028f0f76043ccb1f8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e1d70676406f26d339465fe3473c0c05.png)
(2)求直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d78abbad68bbbf12af10cd40ef4c353.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a28d6477c85c5a4ac410a884e92fbe53.png)
更新时间:2022-11-28 15:51:07
|
相似题推荐
解答题-证明题
|
适中
(0.65)
名校
解题方法
【推荐1】如图所示,四棱柱
中,底面
是以
为底边的等腰梯形,且
.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/3/6d121132-4289-4ad1-b345-bc3d3e517032.png?resizew=240)
(I)求证:平面
平面
;
(Ⅱ)若
,求直线AB与平面
所成角的正弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6e09725691ee7851f54c0dee86b2bf55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b5c4cd264c97c1f261229925cc5a6761.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/09be53cebefa77faa7211ebf9b1a994b.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/3/6d121132-4289-4ad1-b345-bc3d3e517032.png?resizew=240)
(I)求证:平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d3c43aa55fb8c3cee4bc7a92bb20463d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
(Ⅱ)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/98bb6c309a2063ae910551726027f881.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e168672b47d7e64dc1b404f8882c7dcf.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2】在四棱锥
中,底面
为棱形,
交
于
.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/10/12/45a06a80-6022-46c5-aa5a-d9eb5c4feaa4.png?resizew=270)
(1)求证:平面
平面
;
(2)延长
至
,使
,连结
.试在棱
上确定一点
,使
平面
,并求此时
的值.
![](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/2fc99da77f8460ce5858ed89ea7f9e94.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d40b319212a7e7528b053e1c7097e966.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/10/12/45a06a80-6022-46c5-aa5a-d9eb5c4feaa4.png?resizew=270)
(1)求证:平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6d077f6da8b2c00b152d4679aa2ed7f7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8f571a1aac46c6d0cf440c0ec2846bf9.png)
(2)延长
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/895dc3dc3a6606ff487a4c4863e18509.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f88339943a4dbc42dfc19d1c5bca4205.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8695f06047b9d351564a0fc6968a89d4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bd33764ff4efddfe11a98a609753715c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/67825108ba67284ae24eb4780ba65531.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/34be4e71cabf458f17a6cd7f24bc70af.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fc21917e60d158ec5a46cb6d41cfd4d9.png)
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解答题-证明题
|
适中
(0.65)
【推荐3】如图,已知三棱锥
中,
是边长为
的等边三角形,
,
.
![](https://img.xkw.com/dksih/QBM/editorImg/2024/1/8/e5206317-8082-407d-b51b-0c22c459d3d2.png?resizew=179)
(1)求证:平面
平面
;
(2)若M为BD的中点,求二面角
的正弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/891579e7c231584a8e16b8eeff79888e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/95bacae35b6e16a0a33c2bdc6bc07df7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/70c2888dad200ebe6cbc60b7a680ad6e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/32f01c4faacedfe56f5127d6c0cc63cf.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2024/1/8/e5206317-8082-407d-b51b-0c22c459d3d2.png?resizew=179)
(1)求证:平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fcf6dc837ae85207789b94d109c5c2eb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ca67a5b8f69507c8b80379e86f90a8ce.png)
(2)若M为BD的中点,求二面角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8e5424feb7ee793897a1eda83dc90a1e.png)
您最近一年使用:0次
解答题-问答题
|
适中
(0.65)
【推荐1】如图,在几何体
中,上底面
和下底面
均为正方形,
,且平面
平面
,平面
平面
,E为CD的中点.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/10/9/4e1ca60a-d3e8-4ff9-bc73-cedb309f3068.png?resizew=185)
(1)证明:
平面
;
(2)求直线
与平面
所成角的正弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6e09725691ee7851f54c0dee86b2bf55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/632f2bf1cd0435041fa04b01901d1c8c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/450953efb7d8a64365ddf750f167fbfc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/85a2e10a5aebe40a9018d5ee3ade7af8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6678fa8114e790ab348f6ee25dcbec83.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/10/9/4e1ca60a-d3e8-4ff9-bc73-cedb309f3068.png?resizew=185)
(1)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9e16f65c3a318220c2f5baac171bbb61.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5ebb05874eb3353d754af24c9974273e.png)
(2)求直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15dc61d5de97b5a40be925b278ae494c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/657dffbd3623b705f871878fbd9df57e.png)
您最近一年使用:0次
解答题-问答题
|
适中
(0.65)
名校
【推荐2】如图,在四棱锥
中,底面
是菱形,
平面
,平面
平面
.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/1/19/05c77d18-043a-48c5-a50e-299160013648.png?resizew=184)
(1)证明:
;
(2)若
为
上的点,当
与平面
所成角的正弦值最大时,求
的值.
![](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/ccd4fd4b7a4d6b8ca0c5827c055a9ce7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e4aa9084b8fe0fe05c4388d1f835587b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e7b7c83470489253394bd288d7c920df.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/1/19/05c77d18-043a-48c5-a50e-299160013648.png?resizew=184)
(1)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/080db3af81b29ed10144a1c2e2a4fb8a.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0691064b69881b0fd4e8d15a41919bba.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/48f3c9abbd78e9a6840ee5f30381daac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/48f3c9abbd78e9a6840ee5f30381daac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3653ada76ba0c8afe9d57c8e7832c6ed.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0519ba613bf121a2c1bc28c948266d74.png)
您最近一年使用:0次