发布网友 发布时间:2024-10-24 17:28
共2个回答
热心网友 时间:2024-10-28 06:16
证明:(I)∵PA⊥底面ABCD,AD⊥AB,
以A为坐标原点,建立如图所示的空间直角坐标系,
∵AD=DC=AP=2,AB=1,点E为棱PC的中点.
∴B(1,0,0),C(2,2,0),D(0,2,0),P(0,0,2),E(1,1,1)
∴BE=(0,1,1),DC=(2,0,0)
∵BE?DC=0,
∴BE⊥DC;
(Ⅱ)∵BD=(-1,2,0),PB=(1,0,-2),
设平面PBD的法向量m=(x,y,z),
由已赞过已踩过你对这个回答的评价是?评论收起 // 高质or满意or特型or推荐答案打点时间 window.iPerformance && window.iPerformance.mark('c_best', +new Date); F.context('answers')['28823942'] = {uid:"0",imId:"0",isAnonymous:"1",isCurrentUser:"0",mapUrl:"",refer:"",replyAskNum:"",threadId:"11529579569",hasComment:"0",qid:"369080752010655324",raid:"",recommendCanceled:"0"}; F.context('answers')['28823942']['c_timestamp'] = '1519797540'; F.context('answers')['28823942'].encodeUid = '0'; F.context('answers')['28823942'].ext_pack = {"anony_bad_value":"6","anony_good_value":"1","dynamic_optime":"1635201625","dynamic_score_detail":"{\"qua_score\":2227,\"time_score\":\"-60\",\"ide_score\":\"0\",\"pre_score\":1002486}","mode_begintime":"0","mode_qtype":"0","op_uid":"1099017073","reason_2_2":"1","recTime":"1519822652","reco_time":"1519822652","reco_weight":"1","reply_entry":"qb_list_default"}; F.context('answers')['28823942'].bit_pack = {"is_recommend":"1","wap_flag":"0","is_pic_contained":"0","media_flag":"0","help_flag":"0","anonymous":"1","is_really_anonymous":"0","level_new":"1","comment_flag":"0","in_mis":"0","auto_recommend":"0","content_rich_flag":"0","prior_flag":"0","hidden_flag":"0","rec_canceled_flag":"0","mis_flag":"0","file_flag":"0","read_flag":"0","is_challenge":"0","ikaudio_flag":"0","mavin_flag":"0","is_delete_lock":"0","authentic_state":"0","is_compulsory_best":"0","dynamic_stick_flag":"0","video_flag":"0","vote_affirmative":"0","vote_negative":"0","is_video":"0","is_baiduyun":"0","is_yike_card":"0","is_baidumap":"0","is_note":"0"}; 匿名用户
推荐于2018-02-28展开全部碰到这么标准的,直接以A为原点,AB,AD,AP为x,y,z轴建坐标系来做吧本回答被网友采纳已赞过已踩过你对这个回答的评价是?评论收起推荐律师服务:若未解决您的问题,请您详细描述您的问题,通过百度律临进行免费专业咨询其他类似问题2015-02-09如图,在四棱锥P-ABCD中,PA⊥底面ABCD,AD⊥AB...482015-02-08(2014?东昌区二模)如图,四棱锥P-ABCD中,PA⊥底...2015-02-10如图,在四棱锥P-ABCD中,PA⊥底面ABCD,AB⊥AD...62014-09-13如图,在四棱锥P-ABCD中,PA垂直底面ABCD,AD垂直...232015-02-06(2014?雅安三模)如图,四棱锥P-ABCD中,PA⊥底面...22015-02-08如图,在四棱锥P-ABCD中,PA⊥底面ABCD,AB⊥AD...2015-02-08如图,四棱锥P-ABCD中,PA⊥底面ABCD,PC⊥AD....更多类似问题 >为你推荐:特别推荐“网络厕所”会造成什么影响?华强北的二手手机是否靠谱?癌症的治疗费用为何越来越高?新生报道需要注意什么?百度律临—免费法律服务推荐超3w专业律师,24H在线服务,平均3分钟回复免费预约随时在线律师指导专业律师一对一沟通完美完成等你来答换一换帮助更多人下载百度知道APP,抢鲜体验使用百度知道APP,立即抢鲜体验。你的手机镜头里或许有别人想知道的答案。扫描二维码下载×个人、企业类侵权投诉违法有害信息,请在下方选择后提交
类别
色情低俗涉嫌违法犯罪时政信息不实垃圾广告低质灌水我们会通过消息、邮箱等方式尽快将举报结果通知您。
说明
0/200
提交取消领取奖励我的财富值
0
兑换商品--
去登录我的现金
0
提现下载百度知道APP
在APP端-任务中心提现
--
去登录做任务开宝箱累计完成
0个任务
10任务
略略略略…
50任务
略略略略…
100任务
略略略略…
200任务
略略略略…
任务列表加载中...新手帮助如何答题获取采纳使用财富值玩法介绍知道商城合伙人认证您的账号状态正常
感谢您对我们的支持
投诉建议意见反馈账号申诉非法信息举报京ICP证030173号-1 京网文【2023】1034-029号 ©2024Baidu 使用百度前必读 |知道协议| 企业推广
辅 助
模 式
var _hmt = _hmt || []; (function() { var hm = document.createElement("script"); hm.src = "https://hm.baidu.com/hm.js?6859ce5aaf00fb00387e34e4fcc925"; var s = document.getElementsByTagName("script")[0]; s.parentNode.insertBefore(hm, s); })(); window.tt = 1730067928;热心网友 时间:2024-10-28 06:20
碰到这么标准的,直接以A为原点,AB,AD,AP为x,y,z轴建坐标系来做吧