题目
题型:不详难度:来源:
![](http://img.shitiku.com.cn/uploads/allimg/20191105/20191105032611-51440.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191105/20191105032611-30112.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191105/20191105032611-36788.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191105/20191105032612-96708.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191105/20191105032612-51809.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191105/20191105032612-59038.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191105/20191105032612-51704.png)
(1)求证:
![](http://img.shitiku.com.cn/uploads/allimg/20191105/20191105032612-26080.png)
(2)若
![](http://img.shitiku.com.cn/uploads/allimg/20191105/20191105032612-54224.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191105/20191105032612-25883.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191105/20191105032613-48714.png)
答案
![](http://img.shitiku.com.cn/uploads/allimg/20191105/20191105032613-76739.png)
解析
![](http://img.shitiku.com.cn/uploads/allimg/20191105/20191105032611-51440.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191105/20191105032613-56672.png)
∵ DF∥AC,∴
![](http://img.shitiku.com.cn/uploads/allimg/20191105/20191105032613-91155.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191105/20191105032614-16752.png)
又 ∵
![](http://img.shitiku.com.cn/uploads/allimg/20191105/20191105032614-25247.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191105/20191105032612-26080.png)
(2) ∵
![](http://img.shitiku.com.cn/uploads/allimg/20191105/20191105032614-35341.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191105/20191105032614-60977.png)
又
![](http://img.shitiku.com.cn/uploads/allimg/20191105/20191105032615-37942.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191105/20191105032615-22528.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191105/20191105032615-97589.png)
∴
![](http://img.shitiku.com.cn/uploads/allimg/20191105/20191105032615-21904.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191105/20191105032616-41638.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191105/20191105032616-33290.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191105/20191105032616-15793.png)
∴
![](http://img.shitiku.com.cn/uploads/allimg/20191105/20191105032616-88780.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191105/20191105032616-41638.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191105/20191105032617-28985.png)
(1)两直线平行,同位角相等;三角形中有两个角为60°即为等边三角形。
(2)由
![](http://img.shitiku.com.cn/uploads/allimg/20191105/20191105032615-22528.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191105/20191105032615-97589.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191105/20191105032615-21904.png)
核心考点
举一反三
30°,BC=12cm.半圆O以2cm/s的速度从左向右运动,在运动过程中,点D、E始终在直线BC上.设运动时间为t (s),当t=0s时,半圆O在△ABC的左侧,OC=8cm.
![](http://img.shitiku.com.cn/uploads/allimg/20191105/20191105032608-58169.png)
(1)当t为何值时,△ABC的一边所在的直线与半圆O所在的圆相切?
(2)当△ABC的一边所在的直线与半圆O所在的圆相切时,如果半圆O与直径DE围成的区域与△ABC三边围成的区域有重叠部分,求重叠部分的面积.
![](http://img.shitiku.com.cn/uploads/allimg/20191105/20191105032557-17916.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191105/20191105032558-41115.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191105/20191105032558-72244.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191105/20191105032558-72244.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191105/20191105032558-93181.png)
理由是:
![](http://img.shitiku.com.cn/uploads/allimg/20191105/20191105032553-36765.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191105/20191105032553-52224.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191105/20191105032553-76506.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191105/20191105032553-97055.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191105/20191105032554-14903.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191105/20191105032546-56723.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191105/20191105032546-95280.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191105/20191105032547-62621.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191105/20191105032547-61471.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191105/20191105032547-64170.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191105/20191105032547-20348.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191105/20191105032533-53540.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191105/20191105032533-28805.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191105/20191105032534-62876.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191105/20191105032534-37435.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191105/20191105032534-71868.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191105/20191105032534-16217.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191105/20191105032534-14293.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191105/20191105032534-70672.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191105/20191105032534-91839.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191105/20191105032533-53540.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191105/20191105032534-84110.png)
(1)点
![](http://img.shitiku.com.cn/uploads/allimg/20191105/20191105032534-90220.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191105/20191105032534-84110.png)
(2)当点
![](http://img.shitiku.com.cn/uploads/allimg/20191105/20191105032533-53540.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191105/20191105032534-50259.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191105/20191105032534-71868.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191105/20191105032534-84110.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191105/20191105032534-22959.jpg)
最新试题
- 1(本小题满分14分)(1)已知正数x、y满足2x+y=1,求的最小值及对应的x、y值.(2)已知x>-2,求函数的最小值
- 2作家郭敬明曾说过:“喜欢写大量文字的花季雨季的女生,都是孤独的女孩。”其实,也有许多喜欢写作的女孩是活泼可爱、情感丰富的
- 3在学校走廊里通常悬挂“肃静”的警示牌,让学生保持肃静的做法是属于在_______处减弱噪声。
- 4下面是我国四个城市分布示意图,判断下列哪一组是正确的[ ]A.哈尔滨、广州、上海、福州B.兰州、武汉、上海、广州
- 5一位同学说:“春秋的楚辞,吸收了南方民歌精华,采用楚国方言,句式以四言体为主。”他的话违背历史事实的有( )A.1处B.
- 6I prefer _________ some shopping to ________ camping since t
- 7科学家认为,在宇宙的构成中,人类已知物质仅占4%左右,而暗物质几乎是已知物质的6倍,但人类一点未找到它存在的证据。201
- 8If transport costs _____ into consideration at the beginning
- 9我们一生中扮演着相同的角色,承担着不同的责任。[ ]
- 10If there were no subjunctive mood, English _________ much ea
热门考点
- 1如图所示,质量m=0.1kg的小球在细绳的拉力作用下在竖直面内做半径为r=0.2m的圆周运动,已知小球在最高点的速率为v
- 2What really brings us together is a(n) ______ purpose to pro
- 3求函数f(x)=x3-2x2+1,x∈[-1,2]最大值与最小值.
- 4下列各句中,没有语病、句意明确的一句是[ ]A.国务院总理温家宝8月6日主持召开国务院常务会议,会议要求,要在长
- 5He is one of the students who, I am sure, always do ____ bes
- 6假如你遇到下列情境,请运用所学知识写出理由。情境正确做法理由黄某年仅15岁,在一次上网收集学习资料的过程中,无意进入一家
- 7(下图是印度洋(局部)季风和洋流示意图,读图回答下列问题。 (1)乙图中①、②、③处可能形成渔场的是_______
- 8先化简,再求(2a2-5a)-2(3a+5+a2)的值,其中a=-1.
- 9读图,回答问题.(1)写出地理坐标:小红______、______;小明______、______;小刚______、_
- 10有人大代表将城市和农村比喻为人的两条腿。现在农村这条腿短,不补齐这条短腿,就要拖全面建设小康社会的后腿。这反映的哲学道理