设曲线的参数方程为
则对应于
的曲线段的弧长s=______.
参考答案:ln2
解析:
[分析]: 因 [*] 从而,当[*]时曲线的弧微分 [*] 于是,相应曲线段的弧长 [*]
请根据下面短文回答第11~15题: Reading for pleasure is the easiest way to become a better reader in English. It is also the most important way. Some students say they don’t want to read for pleasure. They say they want to use their time to learn the rules of the language and new words. They say that pleasure reading is too easy. Many experts(专家)say pleasure reading is very important for learning English. Dr. Stephen Krashen, a famous expert on learning languages, says that pleasure reading helps you learn many important things about English. Students learn more grammar and more words when they read for pleasure. They also learn more about good writing. Dr. Krashen tells us that pleasure reading helps each student in a different way. Each student needs to learn something different. Pleasure reading makes it possible for each student to learn what he or she needs. Reading for pleasure is not the same as studying. When you read for pleasure, you choose your own books, and you don’t have to remember everything. There are no tests on your pleasure reading books. Pleasure reading will help you: —learn how English speakers use English —read faster in English —find examples of good writing in English —learn new words —learn about the cultures(文化)of English speakers
If you want to easily become good at reading, you should______. [A] do pleasure reading [B] read a lot of grammar books [C] read many story books
书面表达
第16届亚运会将于2010年11月12日至27日在中国广州举行!这是继08年北京
奥运会后我国的又一大体育盛事。作为中学生的我们又该如何去做呢?请你根据
下面的提示写一篇80词左右的英语短文,准备发表在某英语报刊上,短文开头已
给出,不计人总词数。
提示:1.发扬体育精神(follow the sports spirit),奋力拼搏,取得更好的成绩;
2.加强体育锻炼,强健体魄;
3.其他……
As we all know,the 16th Asian Games will be held on November 12-27 jn GuangZhou. This is
another important sports event in China after Beijing Olympic Games.____________________________________________________________________________________________________________________________________________________________________________________________