题目
题型:不详难度:来源:
答案
则PN∥AC,PM∥BD,
且
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022071346-37268.png)
∴∠MPN即是异面直线AC和BD所成的角,
又∵MN=
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022071346-19174.png)
∴∠MPN=600
∴异面直线AC和BD所成的角为600
解析
核心考点
试题【(本小题满分12分)设平面α∥β,两条异面直线AC和BD分别在平面α、β内,线段AB、CD中点分别为M、N,设MN=a,线段AC=BD=2a,求异面直线AC和B】;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/20191022/20191022071336-84661.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022071336-42396.png)
① 若
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022071336-87861.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022071336-31173.png)
③ 若
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022071336-97524.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022071336-94885.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022071337-85591.png)
其中正确命题的个数为( )
A.1 | B.2 | C.3 | D.4 |
如图,四棱锥P—ABCD中,ABCD为矩形,△PAD为等腰直角三角形,∠APD=90°,平面PAD⊥平面ABCD,E、F分别为PC和BD的中点.
(1)证明:EF∥平面PAD;
(2)证明:平面PDC⊥平面PAD.
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022071331-55803.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022071320-82616.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022071320-13813.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022071320-34449.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022071320-20158.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022071320-77127.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022071320-32881.png)
A.![]() | B.![]() | C.![]() | D.![]() |
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022071312-83032.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022071313-12350.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022071313-93985.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022071313-60320.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022071313-39146.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022071313-85302.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022071314-50483.png)
A.3 | B.5 | C.![]() | D.![]() |
如图,在正方体
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022071259-65357.png)
(Ⅰ)求证:
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022071259-55906.png)
(Ⅱ)求证:
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022071259-53256.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022071300-37091.png)
(III)棱
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022071300-40662.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191022/20191022071300-50939.png)
最新试题
- 11956年底三大改造的基本完成,标志着我国新民主主义革命的结束。错误:
- 2某几何体的正视图与侧视图如图所示,若该几何体的体积为,则该几何体的俯视图可以是 [ ]A.
- 3读经纬网示意图,完成下列内容.(1)读出A、B两点的经纬度:A.______,______;B.______,_____
- 4Lincoln’s mother did ___ many books ___ him.A.what she had b
- 5已知定义在R上的函数f(x)是奇函数,且满足f(x+2)+2f(-x)=0;给出下列结论:①f(2)=0②f(x+2)=
- 6表2是从表1中截取的一部分,则 .
- 7在通常情况下,下列用品属于导体的是A.铅笔芯B.陶瓷碗C.绘画橡皮D.玻璃杯
- 8“少年安能长少年,海波尚变为桑田。”唐代诗人李贺的这一诗句体现了[ ]A.运动是永恒的、绝对的和有条件的 B.
- 9下列词语中加点字的读音完全正确的一项是( )(3分)A.中(zhōng)肯遒劲(jìng)浮藻(zǎo)长歌当(dà
- 10There happened to be nobody under the wall when it fell down
热门考点
- 1日本经济发达的主要原因是( )A.人口众多,国内市场大B.本国自然条件优越,资源丰富C.进口原料,出口产品,积极开拓国
- 2观察漫画《逼上梁山》,为了使鱼儿重返家园,你认为下列想法或做法正确的是[ ]①关闭所有致污企业 ②增强环保意识
- 3Sometimes ______English is quite different from ______Englis
- 4阅读下列材料,回答问题。材料一 共产党之占领台湾,势将直接威胁太平洋之安全,并威胁在该区域履行合法而必要之活动的美国部队
- 5发出“给我一个支点,我将翻转地球”豪言的人物是 [ ]A、希罗多德 B、欧几里德 C、亚里士多
- 6细胞内有遗传物质,细胞的控制中心是 ( )A.细胞质B.线粒体C
- 7不等式的正整数解有[ ]A.1个B.2个 C.3个D.4个
- 8若等腰梯形ABCD的上、下底之和为2,并且两条对角线所成的锐角为60°,则等腰梯形ABCD的面积为( )。
- 9【题文】已知 ,则
- 10某河流右岸侵蚀严重,且所在地区一年中有两次太阳直射现象,则该河流位于( )A.赤道B.赤道与南回归线之间C.北回归线D