题干

已知cosα+cosβ=
1
2
,sinα+sinβ=
1
3
,求cos(α﹣β)的值.
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答案(点此获取答案解析)

解:∵cosα+cosβ=
1
2
,sinα+sinβ= 13

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阅读理解

    Here's an interesting fact: Every teenager American seems to have, at some point, appeared drunk or rude online. This generation didn't invent stupidity, of course; it's just the first to post the picture online the entire world to see. And that's the rub: Employers are getting clever at looking you up online. They look at what people post and wonder. Is that new salesperson, the one who made a strange face on collegehumor.com,likely to do the same at a conference?”

    Anything that you put online is public information. This should seem pretty obvious to the generation who grew up on these sites, right? But it's not. When it comes to the Net, young people tend to fell for two traps. One:“ Many of them believe it's truly private, and they'll determine who gets to sec what, and it will stop there.” Wrong! And two: “Their sense of what things will be like in the next stage of their life is not realistic.”

    So what do you do about that picture? Take it down! But what if it is now on other sites? After all, a friend can post your photo elsewhere, and from there, it can be posted on another site. This problem is so common that a new industry has appeared: identity management, which helps people remove embarrassing material.

    The new industry serves to remind us that we've got to be careful out there. Most of us have got drunk or done something we regret. But putting it online is another matter. And for some, it's even become an addiction, one with a nickname: Crackspace. Young or old, students and managers alike turn into exhibitions, putting every aspect of their lives on public display(展示).

    Yes, it can be great fun. But should those of us posting pictures of ourselves dancing in our underwear be given a good comment? In a forgiving, kindly environment, yes. But what about in a business environment? Well, you decide.

同类题5

阅读下文,回答后面的⑴—⑷题。

    这是座旧式的公寓大楼,房间的间量很大,向阳而明亮,走道又宽又黑。楼外是个很大的院子,院门口有间小门房。门房里也住了一户,户主是个裁缝。裁缝为人老实;裁缝的老婆却是个精力充裕、走家串户、爱好说长道短的女人,最喜欢刺探别人家里的私事和隐私。这大楼里家家的夫妻关系、姑嫂纠纷、做事勤懒、工资多少,她都一清二楚。凡她没弄清楚的事情,就要千方百计地打听到;这种求知欲能使愚顽成才。她这方面的本领更是超乎常人,甭说察言观色,能窥见人们藏在心里的念头;单靠嗅觉,就能知道谁家常吃肉,由此推算出这家收入状况。不知为什么,六十年代以来,处处居民住地,都有这样一类人被吸收为“街道积极分子”。使得他们对别人的干涉欲望合法化,能力和兴趣也得到发挥。看来,造物者真的不会荒废每一个人才的。

    尽管裁缝老婆能耐,她却无法获知这对天天从眼前走来走去的极不相称的怪夫妻结合的缘由。这使她很苦恼。好象她的才干遇到了有力的挑战。但她凭着经验,苦苦琢磨,终于想出一条最能说服人的道理:夫妻俩中,必定一方有某种生理缺陷。否则谁也不会找一个比自己身高逆差一头的对象。她的根据很可靠:这对夫妻结婚三年还没有孩子呢!于是团结大楼的人都相信裁缝老婆这一聪明的判断。

    事实向来不给任何人留情面,它打败了裁缝老婆!高女人怀孕了。人们的眼睛不断地瞥向高女人渐渐凸出来的肚子。这肚子由于离地面较高而十分明显。不管人们惊奇也好,置疑也好,困惑也好,高女人的孩子呱呱堕地了。每逢大太阳或下雨天气,两口子出门,高女抱着孩子,打伞的事就落到矮男人身上。人们看他迈着滚圆的小腿、半举着伞儿、紧紧跟在后面滑稽的样子,对他俩居然成为夫妻,居然这样形影不离,好奇心仍然不减当初。各种听起来有理的说法依旧都有,但从这对夫妻身上却得不到印证。这些说法就象没处着落的鸟儿,啪啪地满天飞。裁缝老婆说:“这两人准有见不得人的事。要不他们怎么不肯接近别人?身上有脓早晚得冒出来,走着瞧吧!”果然一天晚上,裁缝老婆听见了高女人家里发出打碎东西的声音。她赶忙以收大院扫地费为借口,去敲高女人家的门。她料定长久潜藏在这对夫妻间的隐患终于爆发了,她要亲眼看见这对夫妻怎样反目,捕捉到最生动的细节。门开了,高女人笑吟吟迎上来,矮丈夫在屋里也是笑容满面,地上一只打得粉碎的碟子——裁缝老婆只看到这些。她匆匆收了扫地费出来后,半天也想不明白这夫妻之间到底发生了什么事。打碎碟子,没有吵架,反而象什么开心事一般快活。怪事!

    后来,裁缝老婆做了团结大院的街道居民代表。她在协助户籍警察挨家查对户口时,终于找到了多年来经常叫她费心的问题答案。一个确凿可信、无法推翻的答案。原来这高女人和她的矮丈夫,都在化学工业研究所工作。矮男人是研究所总工程师,工次达一百八十元之多!高女人只是一名普普通通的化验员,收入不足六十元,而且出生在一个辛苦而赚钱又少的邮递员家庭。不然她怎么会嫁给一个比自己矮一头的男人?为了地位,为了钱,为了过好日子,对!她立即把这珍贵情报,告诉给团结大楼里闲得难受的婆娘们。人们总是按照自己的思维方式去解释世界,尽力把一切事物都和自己的理解力拉平。于是,裁缝老婆的话被大家确信无疑。多年来留在人们心里的谜,一下子被打开了。大家恍然大悟:原来这矮男人是个先天不足的富翁,高女人是个见钱眼开、命里有福的穷娘儿们。当人们谈到这个模样象匹大洋马、却偏偏命好的高女人时,语调中往往带一股气。尤其是裁缝老婆。

⑴.小说描写的环境“团结大楼”有什么特点?