问题 填空题

极坐标方程分别为ρ=cosθ与ρ=sinθ的两个圆的圆心距为______.

答案

由ρ=cosθ,化为直角坐标方程为x2+y2-x=0,其圆心是A(

1
2
,0),

由ρ=sinθ,化为直角坐标方程为x2+y2-y=0,其圆心是B(0,

1
2
),

由两点间的距离公式,得AB=

2
2

故答案为:

2
2

单项选择题
写作题

读写任务

        阅读下面短文,然后按照要求写一篇150词左右的英语短文。

        According to a report from the Entertainment Software Association (ESA), the sale of computer

games in the United States of America has more than doubled in the past 10 years, from $2.6 billion to

$7 billion in 2005. Analysts (分析家) say that these numbers are very alarming and many people are

asking, “Can gaming become an addiction?” Elizabeth Woolly said, “Computer games, like any other

activity, can be hard to stop once an addiction has been formed.”

        Many students are addicted to computer games and they even forget eating and bathing. They don’t

go to school, playing games for hours of days. It is said that last year, seven people in South Korea died as

a result of too much gaming. 

       “We have kids who don’t know how to communicate with people face to face because they have

spent three years playing games and talking to others through a computer. Eventually computer games have

spoiled their eyes,” said a father.

        [写作内容]

        1.用大约30个词概括短文的内容要点。

        2.用120个词就“中学生该不该玩电脑游戏”这个主题发表你的看法,至少包括以下要

点:

        1)你认为中学生该不该玩电脑游戏。

        2)说明你的理由。

        [写作要求]

        你可以使用实例或其它论述方法支持你的论点,也可以参照阅读材料的内容,但不得直

接引用原文中的句子。

        [评分标准]    概括准确,语言规范,内容合适,篇章连贯