如图,在正方体
中,
(1)求证
;
(2)求
与平面
所成角的大小.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6e09725691ee7851f54c0dee86b2bf55.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/8/1/65e29f2e-d2ca-41db-9fb8-21aeb025caa6.png?resizew=149)
(1)求证
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bb81a917e1183890a82885b350b63f14.png)
(2)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b470c4e195cf7a07b7a331ce4b436e03.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ea848cd2aa3a464618020475097949fc.png)
更新时间:2023-07-27 21:13:10
|
相似题推荐
解答题-证明题
|
适中
(0.65)
解题方法
【推荐1】如图,在三棱维
中,
,平面
平面
.
;
(2)求证:
平面
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63397cda22cb1fad59cf966dfb588643.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/73be8deba8ae98bd3874110261be3c57.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e4aa9084b8fe0fe05c4388d1f835587b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e7b7c83470489253394bd288d7c920df.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8a15a004f7d47ed595f063e60075223a.png)
(2)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e2ffc6952e988d04f22f0fb2f7f0ab7b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1e582d73b96ba649378379c3074d506d.png)
您最近一年使用:0次
解答题-证明题
|
适中
(0.65)
名校
【推荐2】如图(
),在直角梯形
中,
,
,且
,取
的中点
,连结
,并将
沿着
翻折,翻折后
,点
分别是线段
的中点,如图(
).
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/16/6f829e67-75b0-42a2-99c6-c84710caf630.png?resizew=349)
(1)求证:
;
(2)求平面
与平面
夹角的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bdaa19de263700a15fcf213d64a8cd57.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/10df84d553a8826a7ce9bff4bf0d95b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/080db3af81b29ed10144a1c2e2a4fb8a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4c1217ec2140f918d37b09769b54ab2a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/683c590673eece14fea3319c4fd5eb55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/372629a8666de1e9bac3e7daadcac7b6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/683c590673eece14fea3319c4fd5eb55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8e1f4f255d191786f7d330d278868c2d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7789a500686c7a73770404ead6af0590.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cea77ba313fcc751481ac1ca214df3fc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/61128ab996360a038e6e64d82fcba004.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/16/6f829e67-75b0-42a2-99c6-c84710caf630.png?resizew=349)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/20bd456411c7e7c1ddd65fef7f79f15f.png)
(2)求平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3e17dc84ba2e871aeb3a3fd2a2b5f1a8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9ab158dd9e96abcae0f115f54fa66c5b.png)
您最近一年使用:0次
解答题-证明题
|
适中
(0.65)
【推荐1】如图,在直三棱柱
中,底面
为正三角形,侧面
为正方形,
,且
,
分别是
,
的中点.
(1)求证:![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411461db15ee8086332c531e086c40c7.png)
平面
;
(2)求直线
与平面
所成角.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/42d3a82b8e587ee890467835bc4e854c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bef5239ddbb0972700ce01daf9ee7cf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2d9a8181f7a7fe7f3fac872ce9534f15.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/af0e44cb429eea46e7ee4320147192b3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54a5d7d3b6b63fe5c24c3907b7a8eaa3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e26d9636ad77369535852c6e4493446a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/56f7ba05c54b3de1f4378f7c8eb58328.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/7/16/0ff2e0ef-ec9c-48c8-9259-97aff2328aeb.png?resizew=148)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411461db15ee8086332c531e086c40c7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/638537c0a30676c73fea76c80e0f8bd0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2d9a8181f7a7fe7f3fac872ce9534f15.png)
(2)求直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c884b508394b3ab50734b584d9ec783c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/99b16cff607cdc2d69afc70dc778acbb.png)
您最近一年使用:0次
解答题-证明题
|
适中
(0.65)
解题方法
【推荐2】如图,正方体
中,点
分别是
中点.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/8/14/7735a646-6cc2-442c-b855-a441ff06a424.png?resizew=196)
(1)求证:
;
(2)求
和平面
所成角的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6e09725691ee7851f54c0dee86b2bf55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7789a500686c7a73770404ead6af0590.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1427950aecc4709a5afe6722127c9a1f.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/8/14/7735a646-6cc2-442c-b855-a441ff06a424.png?resizew=196)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2603fef52d4c7c20ec4628048515bc7a.png)
(2)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e0a851907ada2ac2c3c4880a6736d28a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2b8372f6eba66a0bd3587106daaf68d1.png)
您最近一年使用:0次
解答题-证明题
|
适中
(0.65)
【推荐1】已知四边形
,
,
,将
沿
翻折至
.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/3/ce972e53-2568-418e-9861-e8842e8aa2fe.png?resizew=340)
(Ⅰ)若
,求证:
;
(Ⅱ)若二面角
的余弦值为
,求
与面
所成角的正弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bba797c9497b139a93da88f88a768560.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5cb120e9e138816a803d4690ab6c3863.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4fbfcae2cecc98e2d6c16dde6d3ec1c1.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/3/ce972e53-2568-418e-9861-e8842e8aa2fe.png?resizew=340)
(Ⅰ)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/62974d34de3a12418d6b700420afd1b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d4710f75c66f19825a3e44b48f78bbac.png)
(Ⅱ)若二面角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bc9f1e2b86f4eca37c72011d3dffb0c9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/602baac86c2b1668ecdfadc8a5948885.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e0629ce42392a7fe9be21d25c39c3e64.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)
【推荐2】如图所示的几何体中,已知平面
平面
,
,且
,
,
,求证:![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c3f35646cb29fafd1e1a214b69e4f22d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/617edf7f259f5955db7cad814af85281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/99b16cff607cdc2d69afc70dc778acbb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/36723bd074d43a8c98d9bd416020042c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ae412a4dc9683177e1e484b88bbf51f5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/62c0dc85914e7ca927607e58871d398d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f88e7df45acca3fc3d3da3370f0c32bc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c3f35646cb29fafd1e1a214b69e4f22d.png)
![](https://img.xkw.com/dksih/QBM/2011/3/29/1570083507953664/1570083513458688/STEM/f849be1538414e7e8399bc3352638b6e.png?resizew=148)
您最近一年使用:0次