题干

解方程 x2+2x+1=4;

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答案(点此获取答案解析)

解:解方程 x2+2x﹣3=0,

因式分解,得(x﹣1)(x+3)=0,

于是得x﹣1=0,或x+3=0,

x1=1,x2=﹣3.

同类题1

阅读下列短文,根据短文中的信息完成文后表格。(每空一词)
    Minoru Yamasaki was a well-known American architect (建筑师). He was born in 1912 in Seattle, Washington. Minoru went to college to study architecture. Every summer he worked in a fish factory to help pay for college. He slept in a room with 100 other men.
    Yamasaki sometimes dreamed about his work. Once he woke up at three o'clock in the morning. He remembered a building that was in his dream. He got up and started to draw.  
    Yamasaki was different from other architects. His buildings give people a feeling of peace and happiness. Many of his designs have pools of water, flowers, and windows on the roof to let in light. He wanted to give them a place away from the busy ways of modern life.
    Yamasaki worked for several companies. But his success began when he started his own company. In 1956, he won the Architect's First Honor Award for his design of an airport in St. Louis, Missouri. He won two more awards over the next five years. In 1962, he designed the World Trade Center in New York. In 1993, a bomb exploded (炸弹爆炸) in it. But the buildings did not fall down because they had a good design.
Yamasaki had strong opinions about his buildings. They had to be built his way. He refused to change the design of his buildings, even if he lost a job.
    Minoru Yamasaki died on Jun,2 1986. He designed more than 300 buildings. People will enjoy the design and beauty of his buildings for a very long time.


The title   A     ____  American architect
Be born  In   ____  in Seattle, Washington
In college  Studied  architecture  in college
Worked in a fish factory to ____  for college
  ____  a room with 100 other men
His design of buildings Made people feel  ____  and happy
Had  ____  opinions about his buildings
The World Trade Center didn't fall down after a bomb explosion
Successful  career  Was not the  ____   as other architects
Didn't begin his successful career    ____  he started his own company
Won   ____  Awards for his famous design before 1962 and designed over 300 buildings in his life
Date of  ____    Died on Jun,2  1986

同类题2

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    蔡襄,君谟,兴化仙游人。举进士,为西京留守推官、馆阁校勘。范仲淹以言事去国,余靖论救之,尹洙请与同贬,欧阳修移书责司谏高若讷,由是三人者皆坐谴。襄作《四贤一不肖诗》,都人士争相传写,书者市之,得厚利。契丹使适至,买以归,张于幽州馆。庆历三年,仁宗更用辅相,亲擢靖、修及王素为谏官 , 襄又以诗贺,三人列荐之,帝亦命襄知谏院。襄喜言路开,而虑正人难久立也。乃上疏曰:“朝廷增用谏臣,修、靖、素一日并命,朝野相庆。然任谏非难,听谏为难;听谏非难,用谏为难。三人忠诚刚正,必能尽言。君有过失,不救之于未然,传之天下后世,其事愈不可掩,此之谓彰君过,愿陛下察之,毋使有好谏之名而无其实。”夏竦罢枢密使,韩琦、范仲淹在位,襄言:“陛下罢竦而用琦、仲淹,士大夫贺于朝,庶民歌于路,至饮酒叫号以为欢。且退一邪,进一贤,岂遂能关天下轻重哉?盖一邪退则其类退,一贤进则其类进。众邪并退,众贤并进,海内有不泰乎!虽然,臣切忧之。天下之势,譬犹病者,陛下既得良医矣,信任不疑,非徒病,而又寿民。医虽良术,不得尽用,则病且日深,虽有和【注】、扁,难责效矣。”以母老,求知福州,改福建路转运使,开古五塘溉民田,奏减五代时丁口税之半。进知制诰,迁龙图阁直学士、知开封府。以枢密直学士再知福州。徙知泉州,距州二十里万安渡,绝海而 , 往来畏其险。襄立石为梁,其长三百六十丈,种蛎于础以为固,至今赖焉。又植松七百里以庇道路,闽人刻碑德。治平三年,。明年卒,年五十六。乾道中,赐襄谥曰忠惠。
(节选自《宋史•蔡襄传》)
【注】和:秦和,古代名医。