题干

先化简,再求代数式
x
x
+
2
﹣
x
2
+
2
x
+
1
x
+
2
÷ −−
x
2
1
x
1
的值,其中x= 2 ﹣2.
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答案(点此获取答案解析)

解:原式=
x
x
+
2
﹣

同类题2

任务型阅读

    Sometimes we can get so caught up in the stress and worry of our personal lives that our minds become too confused to operate effectively.This is especially dangerous in a test-taking situation.After hours of reading and studying,our brains can lock up in a state of overload.

    In a stressful situation it's often a must to clear your mind completely to allow your brain to refresh itself and recalibrate all of its functions.But when you're tense,clearing your mind isn't so easy!Try this relaxation technique if you think your brain has seized up from information overload.

    ⒈Set aside at least five minutes for quiet "clearing" time.If you're at school,see if you can put your head down somewhere or find an empty room or quiet space.If necessary,set a watch (or phone) alarm or ask a friend to tap you on the shoulder at a designated time.

    ⒉Think of a time or place that puts you into a complete state of peace.This place will vary from person to person.Have you ever sat on the beach watching the waves come in and realized you've "zoned out" fora while?This is the sort of experience you're looking for.Other experiences that make us zone out could be: Sitting in the dark and staring at Christmas tree lights—remember how peaceful that feels?

    ⒊Cover your eyes and go to your "place".If you are at school preparing for a test before class,you may simply rest your elbows on the desk and put your hands over your eyes.For some people,it may not be a good idea to put your head down.(You might fall asleep!)

    Don't let any thoughts creep into your head.As soon as you start to think about a test problem,clear away the thought and concentrate on your peaceful place.

    ⒋Snap out of it!Remember,this is not nap time.The point here is to refresh your brain.After five or ten minutes of clearing time,take a brisk walk or take a drink of water to re-energize your mind and body.Stay relaxed and resist the urge to think about the things that are stressing you out or clogging your brain.Don't let your brain go back to freeze-out.

    Now go on with your test or study session refreshed and ready!

Title: How to clear your mind to stay relaxed?

Present situation

●We are stuck in stress and worried about our personal lives,stopping our brains working____.

●If you feel stressed,it's often____to clear your mind to leave your brain refreshed.

____to clearing your mind

⒈Set aside at least five minutes for quiet "clearing" time.

●When at school,see if you can put your head down somewhere or stay in a quiet space.

●If necessary,set a watch (or phone) alarm or ask a friend to tap you on the shoulder at a designated time.

⒉Think of a time or place allowing you to feel completely____.

●This place will vary from person to person.

⒊____your eyes and go to your "place".

●When making____for a test at school,you could cover your eyes with your hands to have a rest.

●If you put your head down,you will fall____.

●Make sure not to be____by any thoughts and concentrate on your place.

⒋Snap out of it!

●Clearing time does not____nap time.

●Stay relaxed and avoid the things that made you stressed out.

Conclusion

It's time you____your test or study session refreshed and ready!

同类题3

阅读下列短文,从下面每题的A、B、C、D四个选项中选出最佳答案。

C

     Cultural relics (文物) carry rich history. But sometimes, they seem like something that only older people enjoy. Recently, a CCTV show about cultural relics has taken young people by storm. It's called National Treasure.

     The show has been highly praised on Bilibili.com. This website is believed to be China's biggest pop culture website for young people. So how can a show about relics from hundreds or even thousands of years ago attract so many young viewers?

     The show's 10 episodes (集) show 27 treasures from nine museums across China. Instead of telling the stories and history behind them, the show invites famous actors to act out these stories on stage.

     Actor Wang Kai plays Emperor Qianlong on the show.He meets ancient artists, as well as his father, Emperor Yongzheng, in a dream.They criticize Qianlong's taste in such fancy designs. But Qianlong argues by saying that this kind of design is the best way to show the prosperity of his time.

     This soon became a hot topic online. Screenshots of Wang Kai's performance were made into popular memes. Internet users also compared pictures of vases from the times of Qianlong (1736-1796) and Yongzheng (1678-1735).

     The stars might be part of the reason that young viewers enjoy the show. But it is still the treasures themselves that are the main focus. “The treasures make me so proud of our country and culture”, internet user “Fengshiyuci” wrote on Sina Weibo. “After watching the show, I want to visit all the museums in China,” wrote by another user with the screen name “Pilipalaxiong”.