问题
问答题
计算
答案
参考答案：
解析：设x=sint，则dx=costdt. 当x=0时，t=0；x=1时，，于是
[分析]： 因为式中有形如的无理式，立即设x=asint；若是，则应设x=atant；同理有时，应该x=asect，这是在解答此类题时必须掌握的.
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计算
参考答案：
解析：设x=sint，则dx=costdt. 当x=0时，t=0；x=1时，，于是
[分析]： 因为式中有形如的无理式，立即设x=asint；若是，则应设x=atant；同理有时，应该x=asect，这是在解答此类题时必须掌握的.
| 完型填空。 | |||
| Jerry is the kind of man you love to hate. He is always in a(n) 1 mood (心态) and always has something 2 to say. In his opinion, the bottom line is your choice 3 you live a life. One morning, he did something you are never 4 to do in the restaurant business: he left the back door open and was 5 up at gunpoint by three armed robbers. While trying to open the 6 , with his hand shaking from 7 , he input the wrong code. The robbers beat him and even 8 him. Luckily, Jerry was found 9 quickly after the robbers had fled and he was rushed to the local first aid center. After 18 hours of operation and weeks of good care, he was out of hospital with fragments (碎片) of the bullets still in his body. Jerry told me what happened after he was sent to hospital. He said the doctors were 10 . They kept telling him he was going to be fine and 11 him into the emergency room. But when he saw the 12 on the faces of the doctors and nurses, he got really 13 . In their eyes, he 14 ,"He's dying." He knew he needed to take 15 . There was a big nurse shouting questions at him. She asked if he was allergic (过敏的) to anything, and the doctors and nurses stopped working as they waited for his reply. Jerry 16 for a while and then he decided to live. He took a deep breath and said, "Yes. 17 !" Over their laughter, Jerry told them to operate on him 18 he wouldn't die. Jerry lived, thanks to the skill of his doctors, but also because of his amazing 19 . I learnt from him that every day we have the choice to live fully. Attitude, 20 , is everything. | |||
| ( )1．A.exciting ( )2．A.positive ( )3．A.how ( )4．A.advised ( )5．A.pulled ( )6．A.box ( )7．A.nervousness ( )8．A.knocked ( )9．A.probably ( )10．A.excited ( )11．A.rolled ( )12．A.surprise ( )13．A.scared ( )14．A.knew ( )15．A.notice ( )16．A.thought ( )17．A.Medicine ( )18．A.unless ( )19．A.reply ( )20．A.to be honest | B．good B．funny B．where B．imagined B．put B．safe B．worry B．killed B．relatively B．organized B．carried B．expressions B．embarrassed B．found B．order B．wondered B．Operation B．even if B．attitude B．in that case | C．usual C．new C．whether C．asked C．held C．counter C．unwillingness C．knifed C．merely C．hard-working C．wheeled C．feeling C．disappointed C．meant C．breath C．judged C．Bullets C．as if C．opinion C．after all | D．balanced D．different D．why D．supposed D．done D．door D．pressure D．shot D．reasonably D．great D．forced D．puzzles D．annoyed D．read D．action D．stopped D．Fragments D．before D．determination D．strictly speaking |