题干

已知f(x)是定义在R上的单调递增函数,则下列四个命题:

①若f(x0)>x0,则f[f(x0)]>x0

②若f[f(x0)]>x0,则f(x0)>x0

③若f(x)是奇函数,则f[f(x)]也是奇函数;

④若f(x)是奇函数,则f(x1)+f(x2)=0⇔x1+x2=0,其中正确的有(   )

A:4个

B:3个

C:2个

D:1个

上一题 下一题 0.0难度 选择题 更新时间:2017-11-18 06:05:11

答案(点此获取答案解析)

A

同类题2

阅读下面语言材料,根据材料内容,从下面五个选项中选出能填入文中空缺处的最佳选项,使短文意思通顺、内容完整。

    Growing up is not always easy. When we face difficulties, we should never give up.____

    It is not useful to cry for help. Hong Zhanhui's story of growing from boy to man tells us about this.

    Hong was born in 1982 in a poor family in Henan Province. When he was only 11, his father became badly ill. And one day he came back with a baby girl. The girl was very young and they must spend much time looking after her. However, a year later, Hong's mother left home. ____ So everything fell onto the young boy:to take care of his father and the sister, and to go on to study.

    Although his life was very hard, Hong didn't go away from his father and sister.

    ____ He climbed tall trees to get birds' eggs for his sister. He walked two hours at weekends to the market to buy different things. Then he sold the things around his school to make some money.

    ____To take care of his sister, he worked hard to rent(租) a room near his college for her, and sent her to school every day.

    When people knew Hong's story, he became a hero in people's eyes. Many people wanted to help him. But Hong refused the help from others. He said he felt happy by other's help, but he believed he could take care of his family by himself. ____ 

A. He did a part-time job to look after his family.

B. His life was hard, but he has grown up from boy to man.

C. A few years later, he began to study at a college.

D. She no longer wanted to live such a poor life and face her sick husband.

E. We should try our best to make the life better.

同类题4

阅读下面材料,按要求回答问题。

农村留守儿童,让我为你点亮心灯

【事件陈述】

有这样一个群体:父母为了生计外出到城市打工,他们却留在了家里,与父母相伴的时间微乎其微。这些儿童集中起来,便成了一个特殊的群体——农村留守儿童。

【权威调查】

①留守儿童宣泄烦恼的途径调查:

途径

写日记

和同学(朋友)说

和父母交流

其他

比例

51.2%

23.5%

13.6%

11.7%

【日记选摘】

我打起十二分的精神,背着沉重的水在崎岖的山路上快速行走。一个下午我背了三趟,把一百五十斤水背到了家里。——夏丛艳

想啊!想啊!想啊!想得口水直流三千尺,想吃个包子竟难于上九天!——岳朝龙

今天开家长会,我也给爷爷讲了,可是我爷爷又老又忙,他没有来,而其他的家长差不多来齐了。——杨敏

同学们又买新校服了,我也想买,但是奶奶说爸爸赚的钱要养一大家子人,旧校服就凑合着穿吧。——李志

我们背着水往家走,到了半路,因为那水太重,所以在下坡时,不小心摔倒,把小脚儿都弄肿了。——张雷

晚上外婆在上面的老房子睡,我一个人在下面的新房子睡,晚上有什么风吹草动,我就很害怕。如果妈妈不去打工,我就不用害怕了。——代礼名

刚到学校的时候,我还害怕被杨老师骂,因为昨天为了赶场买菜,我又没去上学,也没有向他请假。我总耽误学习,成绩又不好,这让我很难为情。——杨海

【焦点访谈】

菏泽定陶留守儿童学校校长刘传玺:城里的借读费太贵,所以许多孩子只能留在家里。为了他们,我创办了学校,其中经历了许多辛酸,沉重的经济压力,短缺的师资力量,而现在我们更担心的是留守孩子的身体疾病以及行为上的缺乏管理。

贵州省“山水留守儿童之家”创办者兰成山、兰成水:由于长期远离父母,许多孩子封闭、自卑,哭起来时根本不会喊“爸爸、妈妈”。我们希望为村里的学龄前留守儿童创办一所玩耍和学习的乐园,解决外出务工人员最担心的问题,也希望社会各界齐心协办,帮助改善孩子的学习环境。

成都子云路小学校长李广:由于户籍限制,许多公办学校不接受随迁子女就读。但“孩子读书不能等”,于是我在当地租下旧厂房改造成教室,招聘了18名教师,办了这所民办学校。目前还有许多困难,如围墙和教室墙体不合规定,教室采光严重不足。

【星星点灯】

农民工全国人大代表康厚明:我们农民工也希望将孩子带在身边,但是经常加班,往往一天要工作十五六个小时,孩子在我们身边不是要遭罪吗?没办法,只好让孩子们在老家跟爷爷奶奶一起生活。留守儿童的问题也希望政府能够给予更多关注。

全国政协委员、华中科技大学教授姚凯伦:应该给家庭、学校、社会、政府都界定相关责任,学校应该对留守儿童开展有针对性的心理教育、生存教育、安全教育,细化留守儿童的寄宿管理,充实孩子的业余生活,同时建立留守儿童的跟踪管理档案。

国家心理咨询师刘春燕:有很多夫妻结伴外出打工,孩子留在家里托人看管,很易被社会上不良风气所染,成为问题少年。据调研,在押犯人中曾为留守少年儿童的比例达20.1%。家长应该经常和孩子、学校保持密切联系,全面了解孩子的动态,让孩子感受到关爱。

中国社科院社会学研究所所长陈光金教授:2014年,“异地高考”将大面积实施,各省制定了有条件放开外来务工人员随迁子女参加高考的政策,或将给更多学生带来方便。