题目
题型:不详难度:来源:
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022085808-70627.gif)
成角的正切值为 ( )
A.![]() | B.![]() |
C.1 | D.![]() |
答案
解析
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022085808-51689.gif)
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022085809-77109.gif)
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022085809-45095.gif)
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022085809-75658.gif)
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022085809-94389.gif)
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022085810-67046.gif)
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022085810-25482.gif)
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022085810-86063.gif)
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022085810-26354.gif)
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022085810-51522.gif)
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022085811-10605.gif)
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022085811-24000.gif)
平面上的射影所成的锐角,根据题目的条件作出斜线在该平
面上的射影是实现解题的关键,而作射影的关键则是作出平
面的垂线,要注意面面垂直的性质在作平面的垂线时的应用.
核心考点
举一反三
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022085759-34605.gif)
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022085759-34605.gif)
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022085759-34605.gif)
A.![]() | B.![]() | C.![]() | D.![]() |
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022085747-10339.jpg)
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022085748-41548.gif)
ABCD为正方形,
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022085748-98212.gif)
且
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022085748-21901.gif)
线段PA,PD,CD的中点.
(1)求证:
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022085748-63204.gif)
(2)求异面直线EG与BD所成的角;
(3)在线段CD上是否存在一点Q,
使得点A到面EFQ的距离为0.8. 若存在,
求出CQ的值;若不存在,请说明理由.
如图,在直三棱柱
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022085728-62655.gif)
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022085729-19000.gif)
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022085729-41335.gif)
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022085729-96157.gif)
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022085723-52909.gif)
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022085723-90458.gif)
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022085723-90458.gif)
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022085723-50513.gif)
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022085724-15668.gif)
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022085724-77850.gif)
A.1条 | B.2条 | C.3条 | D.4条 |
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022085718-81763.gif)
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022085718-18657.gif)
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022085719-68295.gif)
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022085719-14803.gif)
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022085719-20267.gif)
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022085719-57100.gif)
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022085719-75200.gif)
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022085720-64616.gif)
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022085720-28224.gif)
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022085720-23378.gif)
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022085720-85441.gif)
A.①② | B.①③ | C.①④ | D.②④ |
最新试题
- 1面积是160平方米的长方形,它的长y米,宽x米之间的关系表达式是[ ]A.y=160xB.y=C .y=160+
- 22005年5月5日,亲民党主席宋楚瑜率领的亲民党访问团将抵达西安。据报道,此次宋楚瑜一行将拜祭中华民族的“人文始祖”,他
- 3The editor the last part of the news report to make i
- 4已知函数f(x)=x3+ax-2,(aR).(l)若f(x)在区间(1,+)上是增函数,求实数a的取值范围;(2)若,且
- 5已知矩形A的边长分别为a和b,如果总有另一矩形B,使得矩形B与矩形A的周长之比与面积之比都等于k,则k的最小值为____
- 6(本小题满分10分)已知抛物线的焦点坐标是F(0,-2), 求它的标准方程。
- 7关于电压、电流、电阻三个量的说法中,正确的是 [ ]A.由U=IR可知,导体两端的电压跟通过它的电流成正比,跟它
- 8下列有关元素性质的递变规律不正确的是( )A.Na、Mg、Al的还原性逐渐减弱B.HCl、PH3、H2S气态氢化物的稳
- 9某人在t=0时刻,开始观察一个正在做匀加速直线运动的物体,现在只测出了该物体在第3s内及第7 s内的位移,则下列说法正确
- 10首字母填空 根据所给字母提示填写对话中所缺的单词 Disneyland is called by kids all o
热门考点
- 1A、B两根粗细相同的不同导线,电阻率之比1:2,长度之比为4:1,则它们的电阻之比RA:RB="__________"
- 2_____ the temperature is, _____ water turns into steam.
- 3(1)已知a为实数,求式子 a+ 92
- 4写作(40分)阅读冰心的一首小诗,根据要求作文。成功的花人们只惊慕她现时的明艳!然而当初她的芽儿,浸透了奋斗的泪泉,洒遍
- 5乐乐做“研究平面镜成像特点”的实验时,如图所示:(1)为了便于观察该实验,最好在______环境中进行(选填“较明亮”或
- 6如图所示,内错角共有( )A.4对B.6对C.8对D.10对
- 7根据句意和首字母提示填空。1. This skirt is too small, I want a l________
- 8“温室效应”是哥奉哈根世界气候变化大会研究的环境问题之一。CO2气体在大气层中具有吸热和隔热的功能,是主要的温室气体。(
- 9已知,若函数不存在零点,则c的取值范围是_________。
- 10如图,AB为⊙O的直径,点C在AB的延长线上,CD、CE分别与⊙O相切于点D、E,若AD=2,∠DAC=∠DCA,则CE