如图，在直三棱柱ABC－A1B1C1中，点M，N分别为线段A1B，AC1的中点．（1）求证：MN∥平面BB1C1C；（2）若D在边BC上，ADDC1，求证：MNAD． 您好，您目前使用的浏览器版本比较旧，无法使用学优题库的新功能，建议您更换firefox或chrome浏览器学优网，成就我的梦想。 |
| 题文如图，在直三棱柱ABC－A1B1C1中，点M，N分别为线段A1B，AC1的中点．（1）求证：MN∥平面BB1C1C；（2）若D在边BC上，AD&DC1，求证：MN&AD． &&微信扫描左侧二维码，可以将本题分享到朋友圈，或者发送给同学或老师寻求帮助。我的答案答案评定：参考答案纠错难度评价：做题心得：我要解析巩固设为直线，是两个不同的平面，下列命题中正确的是（&&）A．若，则B．若，则C．则D．，则&&已知互相垂直的平面交于直线．若直线满足，则（&&）A．B．C．D．&&如图，在三棱锥中，平面平面，，．设，分别为，中点．（1）求证：平面；（2）求证：平面；（3）试问在线段上是否存在点，使得过三点，，的平面内的任一条直线都与平面平行？若存在，指出点的位置并证明；若不存在，请说明理由．&&EY has many fake bloggers, ask yourself why? A username is not just a usename, it a bloggger's
identity irrespective of the fact that it might not b a blogger's real name. Why r there fake blogger's. It is usually recognizable/known bloggers who lack confidence, disillusioned, angry, have low self esteem, afraid of criticism. They r more likely from dysfunctional families where one or both parents were substance abusers n were abusive. Their confidence/self esteem is low as they were subjected 2 numerous forms of abuse. They hate themselves n the world. They have developed destructive n uncontrollable behaviour. Their attention seeking antics r a defense mechanism, as they r compensating
for years of physical n psychological neglect | www.soccerladuma.co.za
Express Yourself
THE PROFILE OF MASK BLOGGERS: GETTING 2 KNOW N UNDERTAND THE KINGS N OTHERS
EY has many fake bloggers, ask yourself why? A username is not just a usename, it a bloggger's
identity irrespective of the fact that it might not b a blogger's real name. Why r there fake blogger's. It is usually recognizable/known bloggers who lack confidence, disillusioned, angry, have low self esteem, afraid of criticism. They r more likely from dysfunctional families where one or both parents were substance abusers n were abusive. Their confidence/self esteem is low as they were subjected 2 numerous forms of abuse. They hate themselves n the world. They have developed destructive n uncontrollable behaviour. Their attention seeking antics r a defense mechanism, as they r compensating
for years of physical n psychological neglect
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EY has many fake bloggers, ask yourself why? A username is not just a usename, it a bloggger's
identity irrespective of the fact that it might not b a blogger's real name. Why r there fake blogger's. It is usually recognizable/known bloggers who lack confidence, disillusioned, angry, have low self esteem, afraid of criticism. They r more likely from dysfunctional families where one or both parents were substance abusers n were abusive. Their confidence/self esteem is low as they were subjected 2 numerous forms of abuse. They hate themselves n the world. They have developed destructive n uncontrollable behaviour. Their attention seeking antics r a defense mechanism, as they r compensating
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