已知空间三点
.求以
为邻边的平行四边形的面积;
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d0d8758fb0f87079bd7a4b6fc9836601.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7dec2ca6438c82b43f746057d8129885.png)
更新时间:2023-10-17 23:36:53
|
【知识点】 空间向量数量积的应用
相似题推荐
解答题-问答题
|
适中
(0.65)
解题方法
【推荐1】设空间两个单位向量
,
与向量
的夹角都等于
,求
的值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/915a3c1b10fd425e2640fc497ddf4b71.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f518e3d6121c92bbc86cc390ab80027b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7dd16057efa63e7685cb6d35051a7da1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/af9955b5aebb73cd84447e8541f901ac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad71547a1a45cc7b11d6ecde59884c7.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,已知平行六面体
中,底面ABCD是边长为
的正方形,侧棱
长为
,
.
(1)求
的长;
(2)证明:
;
(3)求直线
与AC所成角的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6e09725691ee7851f54c0dee86b2bf55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0a6936d370d6a238a608ca56f87198de.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2777840758e70e7dbbc18cef8f3d6d2b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2c94bb12cee76221e13f9ef955b0aab1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7ce64c7cf095a20894e9ddd0d95992a9.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/6/7/660e1e2a-81ef-4fbf-9ee0-258fc7d88838.png?resizew=199)
(1)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/24bb49fdc6b6bbb2449fdf8a0de769d3.png)
(2)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0aa142bb96af98b846997e681609739f.png)
(3)求直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9fe734023d4e70010a6b2cc3267cb86e.png)
您最近一年使用:0次