题干

已知二次函数y=ax2+bx+c的x、y的部分对应值如下表:

x

﹣1

0

1

2

3

y

5

1

﹣1

﹣1

1

则该二次函数图象的对称轴为(   )

A:y轴

B:直线x= 52

C:直线x=2

D:直线x= 32

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答案(点此获取答案解析)

D

同类题1

阅读理解

    Our “Mommy and Me” time began two years ago. My next-door neighbor and fellow mother, Christie, and I were out in our front yards, watching seven children of age 6 and under ride the bikes up and down. “I wish I could take one of my children out alone,” said Christie.

    Then we worked out a plan: When Christie takes one of her children out, I'll watch her other three. And when she watches two of mine. I'll take someone out.

    The children were extremely quick to accept the idea of “Mommy and Me” time. Christie's daughter, McKenzie, went first. When she returned, the other children showered her with tons of questions. McKenzie was smiling broadly. Christie looked refreshed and happy. “She's like a different child when there's no one else around,” Christie shared with me quickly. With her mother all to herself, McKenzie didn't have to make an effort to gain attention.

    Just as Christie had noticed changes in McKenzie, I also discovered something different in each of my children. For example, I am always surprised when my daughter, who is seldom close to me, holds my hand frequently. My stuttering (口吃的) son, Tom, doesn't stutter once during our activities since he doesn't have to struggle for a chance to speak. And another son, Sam, who's always a follower when around other children shines as a leader during our times together.

    The “Mommy and Me” time allows us to be simply alone and away with each child-talking, sharing, and laughing, which has been the biggest gain. Every child deserves to be an only child at least once in a while.

同类题3

课外文学作品阅读

一支倾听黑暗的蜡烛

朱成玉

    ①临终时,祖母颤巍巍地示意我们点上一根儿蜡烛,说要和它一起熄灭。

    ②祖母望着蜡烛,眉头舒展,窃贼瞄见金子一般,灵光乍现,随即又仿佛一个跋涉了许久的旅人到达了目的地,长舒一口气,卸下所有。

    ③祖母没有活过那根蜡烛,先它一步,咽了气。祖母的脸上露出久违的微笑,酒窝像一朵莲花。她奋力伸出手去,骨瘦如柴的手,指着我们。像菩萨的手,伸到我们中间。

    ④祖母去了,电却来了,电灯照亮所有人的忧伤,却再也照不亮祖母的前额。

    ⑤父亲吹灭了蜡烛,说,“留着这根蜡烛,等出灵的时候,点着它,给你奶奶在那边照个亮儿。那边太黑了。”

    ⑥那边是哪边?父亲又没去过,怎么就知道那边是黑的?年少的我满是疑惑,可是看着一张张因为悲伤而严肃异常的脸,我又不敢问太多。

    ⑦父亲似乎看出我的疑惑,接着说,“你奶奶这一辈子苦啊,在晦暗的地方呆得时间太长了。”

    ⑧祖父和祖母结婚一年后便当了兵,然后杳无音讯,祖母一生没有再嫁,独自一人养大父亲和叔叔。因为祖父当的是国民党兵,所以文革的时候免不了受了很多红卫兵的“声讨”和欺辱。祖母忍受着尘世带给她的一切苦楚,正如她那苦命的村庄,终日沉默,一言不发。只有无限猛烈的狂风抽打它时,它才勉强挣扎一下。

    ⑨她在村庄里扎下根去,哪都不去。她说就算临死前最后一刻,也要等着祖父,她就那么执拗地信着,祖父还活着。

    ⑩那段日子,祖母常常去当铺。从最开始的手镯,到后来的银饰,甚至她最割舍不下的香炉,银制的烟袋锅,都一一典当出去,只为了让她的孩子们不挨饿。为了孩子,她把自己典当得干干净净,空剩一副嶙峋的瘦骨。

    ⑪老了,本想着该享享清福,却不想又得了重疾。

    ⑫祖母是个极其干净的人,大家闺秀,年轻时候有洁癖,她的床,别人坐过之后,她都要重新洗一遍。每天会洗好几遍手和脸,爱用香皂。可是她老了,病了,臭气在体内发生。她的所有器官都坏了,功能丧失,大便经常要由父亲和叔叔轮流用手指头抠出来。每当这时候,祖母只能无可奈何地拉被子遮脸。有时候她会像疯子一样发火,有时候会像小孩一样哭。一生的尊严和坚守,劈哩啪啦全毁了。

    ⑬最难熬的是夜。一切都停了下来,唯独疼痛,还在漫无边际地爬。

    ⑭祖母在黑暗中,忍着疼痛,她的手紧紧攥着,她的嘴紧紧咬着被子,她不喊叫,她心疼她的儿孙,不想让自己的喊叫惊醒了我们。

    ⑮祖母在黑暗中,被疼痛戳醒,就那么睁着眼睛,我想,她的脑海中定是一遍一遍地播放着往日时光,这岁月的皮影戏,终于要演到最后一幕。

    ⑯令我们意想不到的,祖母在黑暗里对抗疼痛的方式,竟然是给我们一颗颗地嗑着瓜子,早上醒来,她的枕头边儿上堆满了很大的一堆瓜子瓤。只有早晨这会儿,她才能睡一会儿,我们轻手轻脚,从她的枕头边搬走一座山,尽量不弄出一点儿声响来。

    ⑰想起父亲说的话,祖母更多的时光都是在黑暗里,而她并没有因此消沉,照样带领我们把日子过得柳暗花明,风生水起。说白了,祖母是一个可以驾驭苦难的人,苦难这烈马,一旦驯服,可以驮一个人奔往幸福

    ⑱在黑暗里又怎样?那就去做一支倾听黑暗的蜡烛。

    ⑲这是祖母的哲学。

    ⑳终于知道祖母为何在临终前执意要点上一根蜡烛,她是需要这根蜡烛为她送行。她不想,临死前的最后一刻,都是黑暗的啊!

    ㉑想起祖母的这个夜里,我把灯关上,点燃一支蜡烛。倾听黑暗的蜡烛,时儿被风吹熄,时而被风吹亮。忽明忽暗的蜡烛,是奄奄一息的祖母,为了祖父和她的孩子们,咯尽了最后一滴血。

    ㉒夜里的云朵在窗玻璃上颤抖着,想借点光亮取暖,捎带着擦亮了属于思念的小半个天空