在正方体
中.
![](https://img.xkw.com/dksih/QBM/2020/2/12/2397643038875648/2398229448925184/STEM/15f11493da76443fb5404490140ddda4.png?resizew=198)
(1)求证:
;
(2)
是
中点时,求直线
与面
所成角.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6e09725691ee7851f54c0dee86b2bf55.png)
![](https://img.xkw.com/dksih/QBM/2020/2/12/2397643038875648/2398229448925184/STEM/15f11493da76443fb5404490140ddda4.png?resizew=198)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6f217a2438de689a0476f63e8d8f380c.png)
(2)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/19ef601ca1f9c4c031adab4ffed297f0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c33c6587f6e6ec7e400046516bb2c015.png)
更新时间:2020-02-13 17:53:12
|
相似题推荐
解答题-问答题
|
适中
(0.65)
名校
【推荐1】如图,已知多面体
中,
,
平面
,
,
,
,
.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/1/6/77d0ea08-1a33-4893-9fa9-28dc3bd458f0.png?resizew=146)
(Ⅰ)证明:
平面
;
(Ⅱ)求直线
与平面
所成角的正弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ea1e3a43d0fa18f6c0888ba804d5b329.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0facf189b2a3153beb7b9e077d3b1146.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ca5dd496ee0c1170ef6dcc48266ee444.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1e582d73b96ba649378379c3074d506d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5d5ba108d7d2d4807f2c74a22e536fe9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ced06b71073e1bb777f326f06016ce17.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0b80ee363635d73f601654339028daec.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/42e12bfde565540f059dd27ea47dfaa7.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/1/6/77d0ea08-1a33-4893-9fa9-28dc3bd458f0.png?resizew=146)
(Ⅰ)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c45fbffb9e2c7fa7c5006cde8da0cabe.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
(Ⅱ)求直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bd33764ff4efddfe11a98a609753715c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/80f747eb5b2d21c9de962cbfd4ec4bb7.png)
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解答题-证明题
|
适中
(0.65)
名校
解题方法
【推荐2】如图,在四棱锥P-ABCD中,底面ABCD为平行四边形,
为等边三角形,平面
平面PCD,
,CD=2,AD=3,棱PC的中点为N,连接DN.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/29/9d472d62-2735-437d-9b63-3efe68651d26.png?resizew=198)
(1)求证:
平面PCD;
(2)求直线AD与平面PAC所成角的正弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/177678001b2ccde1db8f57fa5e017002.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6d077f6da8b2c00b152d4679aa2ed7f7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b44f4120c94cb7176dc31fcac387b32e.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/29/9d472d62-2735-437d-9b63-3efe68651d26.png?resizew=198)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ccd4fd4b7a4d6b8ca0c5827c055a9ce7.png)
(2)求直线AD与平面PAC所成角的正弦值.
您最近一年使用:0次
解答题-问答题
|
适中
(0.65)
名校
解题方法
【推荐1】如图,已知,四边形ABCD为长方形,平面PDC⊥平面ABCD,PD=PC=4,AB=6,BC=3.
(2)证明:求点C到平面PDA的距离.
(2)证明:求点C到平面PDA的距离.
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,在各棱长均为2的正三棱柱
中,
分别为棱
与
的中点,
为线段
上的动点,其中,
更靠近
,且
.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/10/31/94baf675-cad5-4a4e-a02a-f9409da685c2.png?resizew=226)
(1)证明:
平面
;
(2)若
与平面
所成角的正弦值为
,求异面直线
与
所成角的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/42d3a82b8e587ee890467835bc4e854c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/91e1e4115d78e625e9e0f47cdade3286.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/11ddc92d84d188c66b435664a7e7b5a4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e0a851907ada2ac2c3c4880a6736d28a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7789a500686c7a73770404ead6af0590.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/93ecad355286188fd317939fa50f9555.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3078e4846d090bd29ed2a51c88c8a5eb.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/10/31/94baf675-cad5-4a4e-a02a-f9409da685c2.png?resizew=226)
(1)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c4525c00ed908bed8ba8d353e747a858.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/41104641f3e2260d00aeadf8fb8a078a.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b5d8e33929752b1cb4dd36ee9b98b45d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e168672b47d7e64dc1b404f8882c7dcf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54a850da74554b37e46847692bf62c9d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e69d2b798744645af88a4fa411344a83.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b5d8e33929752b1cb4dd36ee9b98b45d.png)
您最近一年使用:0次