题目
题型:不详难度:来源:
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022042030-12995.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022042031-16364.png)
① 分别作△BAD和△CAD的边AD上的高,则这两条高所在直线异面;
② 分别作△BAD和△CAD的边AD上的高,则这两条高相等;
③
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022042031-73000.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022042031-30800.png)
④
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022042031-20507.png)
其中正确的命题有__________________,
答案
解析
试题分析:如图作
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022042031-83120.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022042032-22628.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022042032-62384.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022042032-30423.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022042032-53866.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022042032-54706.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022042033-56168.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022042033-35592.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022042033-76815.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022042033-30166.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022042034-45571.png)
核心考点
试题【在三棱锥A-BCD中,且.给出下列命题:① 分别作△BAD和△CAD的边AD上的高,则这两条高所在直线异面;② 分别作△BAD和△CAD的边AD上的高,则这两条】;主要考察你对线线角等知识点的理解。[详细]
举一反三
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022042018-71088.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022042018-28299.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022042018-13033.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022042018-51604.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022042019-67938.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022042019-91920.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022042019-89919.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022042018-28299.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022042019-25697.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022042018-51604.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022042020-57241.png)
①平面
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022042020-10602.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022042018-28299.png)
②
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022042020-18633.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022042020-99820.png)
③三棱锥
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022042021-46552.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022042021-77183.png)
④动点
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022042021-70443.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022042018-28299.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022042018-13033.png)
⑤二面角
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022042021-67413.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022042021-34998.png)
其中正确的命题是 (写出所有正确命题的编号).
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022042009-70929.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022042009-24320.png)
A.![]() ![]() ![]() | B.![]() ![]() ![]() |
C.![]() ![]() | D.![]() ![]() |
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022041957-49091.png)
(Ⅰ)证明:MN//平面ABC;
(Ⅱ)若AB=1,AC=AA1=
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022041957-14547.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022041948-38184.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022041949-49940.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022041949-55186.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022041949-72375.png)
(Ⅰ)求证:
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022041949-50480.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022041949-61845.png)
(Ⅱ)求证:平面
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022041950-89542.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022041950-13483.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022041935-29582.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022041935-34250.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022041935-32514.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022041935-40419.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022041936-96889.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022041935-34250.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022041936-58598.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022041936-78982.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022041936-39915.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022041937-99661.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022041937-96251.png)
(Ⅰ)证明:
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022041937-74560.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022041937-46957.png)
(Ⅱ)证明:平面
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022041937-36357.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022041937-46957.png)
(Ⅲ)求四棱锥
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022041935-29582.png)
最新试题
- 1《说苑•正谏》中有这样一段记载:“园中有树,其上有蝉;蝉高居悲鸣饮露,不知螳螂在其后也;螳螂委身曲附,欲取蝉而不知黄雀在
- 2— Hello! ______, can I speak to Danny please? — Sorry, he is
- 3如果汽车安装车轮防抱死装置,则紧急刹车时可获得比车轮抱死时更大的制动力,从而使刹车距离大大减小,而减少刹车距离则是避免交
- 4如图所示,矩形线框的质量m=0.016kg,长L=0.5m,宽d=0.1m,电阻R=0.1Ω.从离磁场区域高h1=5m处
- 5下列四幅图片反映了中外历史上的四次思潮,它们共同具有的主要作用是①②③④
- 6小光在平面直角坐标系中画出了一个长方形,若他想把这个长方形向左平移3个单位长度,他应该______;若他将此长方形的四个
- 7今欲制得50t含铁98%的生铁,需要含杂质10%的赤铁矿(主要成分是Fe2O3)多少吨?
- 8-2的绝对值是( )A.-2B.2 C.-D.
- 9已知椭圆两焦点F1、F2在y轴上,短轴长为2,离心率为,P是椭圆在第一象限弧上一点,且,过P作关于直线F1P对称的两条直
- 10促使日本宣布无条件投降的条件不包括[ ]A.苏联红军进攻东北的日军B.美国向日本投掷原子弹C.国民党军队正面战场
热门考点
- 1“十一五”规划中将“中国扶贫”改为“促进共同富裕”,再次提出了“让一部分人、一部分地区先富起来,最终走共同富裕的道路”。
- 2下列各项反映了土地私有制开始形成的是 ( )A.井田制的推行 B.管仲的改革 C.李悝的变法D.
- 3在等式中,实数的取值范围是A.B.C.D.
- 4给出下列命题:(1)“数列为等比数列”是“数列为等比数列”的充分不必要条件;(2)“”是“函数在区间上为增函数”的充要条
- 5镉元素(Cd)对水体会造成重金属污染。某工业废水中含有三氯合镉酸钾(KCdCl3),其中镉元素的化合价是A.-1B.+1
- 6如果不等式组有解,那么m的取值范围是 ( ▲ )A.B.C.D.
- 7某块实验田里的农作物每天的需水量y(千克)与生长时间x(天)之间的关系如折线图所示,这些农作物在第10天、第30天的需水
- 8水平地面上有一个坑,其竖直截面为半圆。ab为沿水平方向的直径。若在a点以初速度v0沿ab方向抛出一小球, 小球会击中坑壁
- 9如图,在数轴上,A,B两点之间表示整数的点有( )个。
- 10He asked__________for a violin.A.did I pay how muchB.I paid