题干

将(a-1)2-1分解因式,结果正确的是(   )

A:a(a-1)

B:a(a-2)

C:(a-2)(a-1)

D:(a-2)(a+1)

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答案(点此获取答案解析)

B

同类题3

阅读理解

    Jeanne Calment, a French woman, became a record breaker on 17 October of 1995, when at the age of 120 years and 238 days, she became the longest-lived human being on record. A Japanese man died in 1986 at the age of 120 years and 237 days.

    Jeanne Calment lives in a small old people's home in the south of France; her husband, her only child and her grandson have all died. She is nearly blind and deaf and is always in a wheelchair, but her doctor describes her as being more like a 90-year-old in good health than someone of 120. She still has a lively sense of humor. When asked on her 120th birthday what she expected of the future, she replied: A very short one. She also remarked that she thought the good Lord had forgotten all about her.

    So what is the key to a long life? According to some doctors, diet, exercise and no smoking are the three important factors. Jeanne Calment has followed two of the tips. She has always eaten a healthy diet, and she used to do exercise every day until she broke her leg at the age of 115. However, until recently she drank two glasses of strong red wine a day, and she does smoke (now only a little). Besides, Jeanne Calment might have got very good genes from her parents. Her father lived to the age of 94 and her mother to 86.

    A local lawyer bought her house when she was 80 under an agreement that he would pay her some money every year until her death. It must have seemed a good move at the time, but so far the lawyer has paid her at least three times the value of the house. Every year on her birthday Jeanne Calment sends him a card saying: Sorry, I'm still alive!

同类题5

阅读《藤野先生》选段,完成后面小题。

       东京也无非是这样。上野的樱花烂熳的时节,望去确也像绯红的轻云,但花下也缺不了成群结队的“清国留学生”的速成班,头顶上盘着大辫子,顶得学生制帽的顶上高高耸起,形成一座富士山。也有解散辫子,盘得平的,除下帽来,油光可鉴,宛如小姑娘的发髻一般,还要将脖子扭几扭。实在标致极了。

       中国留学生会馆的门房里有几本书买,有时还值得去一转;倘在上午,里面的几间洋房里倒也还可以坐坐的。但到傍晚,有一间的地板便常不免要咚咚咚地响得震天,兼以满房烟尘斗乱;问问精通时事的人,答道,“那是在学跳舞。”

       到别的地方去看看,如何呢?

       我就往仙台的医学专门学校去。从东京出发,不久便到一处驿站,写道:日暮里。不知怎地,我到现在还记得这名目。其次却只记得水户了,这是明的遗民朱舜水先生客死的地方。仙台是一个市镇,并不大;冬天冷得利害;还没有中国的学生。

       从此就看见许多陌生的先生,听到许多新鲜的讲义。解剖学是两个教授分任的。最初是骨学。其时进来的是一个黑瘦的先生,八字须,戴着眼镜,挟着一叠大大小小的书。一将书放在讲台上,便用了缓慢而很有顿挫的声调,向学生介绍自己道:

       “我就是叫作藤野严九郎的……”

       后面有几个人笑起来了。他接着便讲述解剖学在日本发达的历史,那些大大小小的书,便是从最初到现今关于这一门学问的著作。起初有几本是线装的;还有翻刻中国译本的,他们的翻译和研究新的医学,并不比中国早。

       那坐在后面发笑的是上学年不及格的留级学生,在校已经一年,掌故颇为熟悉的了。他们便给新生讲演每个教授的历史。这藤野先生,据说是穿衣服太模胡了,有时竟会忘记带领结;冬天是一件旧外套,寒颤颤的,有一回上火车去,致使管车的疑心他是扒手,叫车里的客人大家小心些。

       他们的话大概是真的,我就亲见他有一次上讲堂没有带领结。

       过了一星期,大约是星期六,他使助手来叫我了。到得研究室,见他坐在人骨和许多单独的头骨中间,——他其时正在研究着头骨,后来有一篇论文在本校的杂志上发表出来。

       “我的讲义,你能抄下来么?”他问。

       “可以抄一点。”

       “拿来我看!”

       我交出所抄的讲义去,他收下了,第二三天便还我,并且说,此后每一星期要送给他看一回。我拿下来打开看时,很吃了一惊,同时也感到一种不安和感激。原来我的讲义已经从头到末,都用红笔添改过了,不但增加了许多脱漏的地方,连文法的错误,也都一一订正。这样一直继续到教完了他所担任的功课:骨学,血管学,神经学。

       可惜我那时太不用功,有时也很任性。还记得有一回藤野先生将我叫到他的研究室里去,翻出我那讲义上的一个图来,是下臂的血管,指着,向我和蔼的说道:

       “你看,你将这条血管移了一点位置了。——自然,这样一移,的确比较的好看些,然而解剖图不是美术,实物是那么样的,我们没法改换它。现在我给你改好了,以后你要全照着黑板上那样的画。”

       但是我还不服气,口头答应着,心里却想道:

       “图还是我画的不错;至于实在的情形,我心里自然记得的。”

       学年试验完毕之后,我便到东京玩了一夏天,秋初再回学校,成绩早已发表了,同学一百余人之中,我在中间,不过是没有落第。这回藤野先生所担任的功课,是解剖实习和局部解剖学。

       解剖实***概一星期,他又叫我去了,很高兴地,仍用了极有抑扬的声调对我说道:“我因为听说中国人是很敬重鬼的,所以很担心,怕你不肯解剖尸体。现在总算放心了,没有这回事。”

       但他也偶有使我很为难的时候。他听说中国的女人是裹脚的,但不知道详细,所以要问我怎么裹法,足骨变成怎样的畸形,还叹息道,“总要看一看才知道。究竟是怎么一回事呢?”