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【330523】第5章《分式与分式方程》单元测试试卷及答案

时间:2025-02-09 11:36:45 作者: 字数:4534字

5章《分式与分式方程》单元测试试卷及答案(2

(时间:90分钟,满分:100)

一、选择题(每小题4分,共32)

1.在代数式 <a href="/tags/1/" title="单元" class="c1" target="_blank">单元</a> <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/46/" title="答案" class="c1" target="_blank">答案</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/380/" title="方程" class="c1" target="_blank">方程</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> <a href="/tags/1/" title="单元" class="c1" target="_blank">单元</a> <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/46/" title="答案" class="c1" target="_blank">答案</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/380/" title="方程" class="c1" target="_blank">方程</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> ,-0.5xy <a href="/tags/1/" title="单元" class="c1" target="_blank">单元</a> <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/46/" title="答案" class="c1" target="_blank">答案</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/380/" title="方程" class="c1" target="_blank">方程</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> <a href="/tags/1/" title="单元" class="c1" target="_blank">单元</a> <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/46/" title="答案" class="c1" target="_blank">答案</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/380/" title="方程" class="c1" target="_blank">方程</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> <a href="/tags/1/" title="单元" class="c1" target="_blank">单元</a> <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/46/" title="答案" class="c1" target="_blank">答案</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/380/" title="方程" class="c1" target="_blank">方程</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> <a href="/tags/1/" title="单元" class="c1" target="_blank">单元</a> <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/46/" title="答案" class="c1" target="_blank">答案</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/380/" title="方程" class="c1" target="_blank">方程</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> 中,是分式的有(  )

A1 B2 C3 D4

2.下列各式从左到右的变形正确的是(  )

A <a href="/tags/1/" title="单元" class="c1" target="_blank">单元</a> <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/46/" title="答案" class="c1" target="_blank">答案</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/380/" title="方程" class="c1" target="_blank">方程</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> B <a href="/tags/1/" title="单元" class="c1" target="_blank">单元</a> <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/46/" title="答案" class="c1" target="_blank">答案</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/380/" title="方程" class="c1" target="_blank">方程</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a>

C <a href="/tags/1/" title="单元" class="c1" target="_blank">单元</a> <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/46/" title="答案" class="c1" target="_blank">答案</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/380/" title="方程" class="c1" target="_blank">方程</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> D <a href="/tags/1/" title="单元" class="c1" target="_blank">单元</a> <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/46/" title="答案" class="c1" target="_blank">答案</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/380/" title="方程" class="c1" target="_blank">方程</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a>

3.计算 <a href="/tags/1/" title="单元" class="c1" target="_blank">单元</a> <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/46/" title="答案" class="c1" target="_blank">答案</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/380/" title="方程" class="c1" target="_blank">方程</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> 的结果是(  )

A <a href="/tags/1/" title="单元" class="c1" target="_blank">单元</a> <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/46/" title="答案" class="c1" target="_blank">答案</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/380/" title="方程" class="c1" target="_blank">方程</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> B <a href="/tags/1/" title="单元" class="c1" target="_blank">单元</a> <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/46/" title="答案" class="c1" target="_blank">答案</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/380/" title="方程" class="c1" target="_blank">方程</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a>

C <a href="/tags/1/" title="单元" class="c1" target="_blank">单元</a> <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/46/" title="答案" class="c1" target="_blank">答案</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/380/" title="方程" class="c1" target="_blank">方程</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> D <a href="/tags/1/" title="单元" class="c1" target="_blank">单元</a> <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/46/" title="答案" class="c1" target="_blank">答案</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/380/" title="方程" class="c1" target="_blank">方程</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a>

4.计算 <a href="/tags/1/" title="单元" class="c1" target="_blank">单元</a> <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/46/" title="答案" class="c1" target="_blank">答案</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/380/" title="方程" class="c1" target="_blank">方程</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> 的结果为(  )

A <a href="/tags/1/" title="单元" class="c1" target="_blank">单元</a> <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/46/" title="答案" class="c1" target="_blank">答案</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/380/" title="方程" class="c1" target="_blank">方程</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> B <a href="/tags/1/" title="单元" class="c1" target="_blank">单元</a> <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/46/" title="答案" class="c1" target="_blank">答案</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/380/" title="方程" class="c1" target="_blank">方程</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a>

C <a href="/tags/1/" title="单元" class="c1" target="_blank">单元</a> <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/46/" title="答案" class="c1" target="_blank">答案</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/380/" title="方程" class="c1" target="_blank">方程</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> D <a href="/tags/1/" title="单元" class="c1" target="_blank">单元</a> <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/46/" title="答案" class="c1" target="_blank">答案</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/380/" title="方程" class="c1" target="_blank">方程</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a>

5.下列分式方程有解的是(  )

A. <a href="/tags/1/" title="单元" class="c1" target="_blank">单元</a> <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/46/" title="答案" class="c1" target="_blank">答案</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/380/" title="方程" class="c1" target="_blank">方程</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> B. <a href="/tags/1/" title="单元" class="c1" target="_blank">单元</a> <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/46/" title="答案" class="c1" target="_blank">答案</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/380/" title="方程" class="c1" target="_blank">方程</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> 0

C. <a href="/tags/1/" title="单元" class="c1" target="_blank">单元</a> <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/46/" title="答案" class="c1" target="_blank">答案</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/380/" title="方程" class="c1" target="_blank">方程</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> D. <a href="/tags/1/" title="单元" class="c1" target="_blank">单元</a> <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/46/" title="答案" class="c1" target="_blank">答案</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/380/" title="方程" class="c1" target="_blank">方程</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> 1

6.按下列程序计算,当a=-2时,最后输出的答案是(  )

 <a href="/tags/1/" title="单元" class="c1" target="_blank">单元</a> <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/46/" title="答案" class="c1" target="_blank">答案</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/380/" title="方程" class="c1" target="_blank">方程</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a>

A <a href="/tags/1/" title="单元" class="c1" target="_blank">单元</a> <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/46/" title="答案" class="c1" target="_blank">答案</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/380/" title="方程" class="c1" target="_blank">方程</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> B <a href="/tags/1/" title="单元" class="c1" target="_blank">单元</a> <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/46/" title="答案" class="c1" target="_blank">答案</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/380/" title="方程" class="c1" target="_blank">方程</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a>

C.-1 D <a href="/tags/1/" title="单元" class="c1" target="_blank">单元</a> <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/46/" title="答案" class="c1" target="_blank">答案</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/380/" title="方程" class="c1" target="_blank">方程</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a>

7.已知ab为实数,且ab1,设M <a href="/tags/1/" title="单元" class="c1" target="_blank">单元</a> <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/46/" title="答案" class="c1" target="_blank">答案</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/380/" title="方程" class="c1" target="_blank">方程</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a>N <a href="/tags/1/" title="单元" class="c1" target="_blank">单元</a> <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/46/" title="答案" class="c1" target="_blank">答案</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/380/" title="方程" class="c1" target="_blank">方程</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> ,则MN的大小关系是(  )

AMN BMN

CMN D.无法确定

8.某工程限期完成,甲队独做正好按期完成,乙队独做则要延期3天完成.现两队先合做2天,再由乙队独做,也正好按期完成.如果设规定的期限为x天,那么根据题意可列出方程:① <a href="/tags/1/" title="单元" class="c1" target="_blank">单元</a> <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/46/" title="答案" class="c1" target="_blank">答案</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/380/" title="方程" class="c1" target="_blank">方程</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a>1;② <a href="/tags/1/" title="单元" class="c1" target="_blank">单元</a> <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/46/" title="答案" class="c1" target="_blank">答案</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/380/" title="方程" class="c1" target="_blank">方程</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> ;③ <a href="/tags/1/" title="单元" class="c1" target="_blank">单元</a> <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/46/" title="答案" class="c1" target="_blank">答案</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/380/" title="方程" class="c1" target="_blank">方程</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> ;④ <a href="/tags/1/" title="单元" class="c1" target="_blank">单元</a> <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/46/" title="答案" class="c1" target="_blank">答案</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/380/" title="方程" class="c1" target="_blank">方程</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> .其中正确的个数为(  )

A1 B2 C3 D4

二、填空题(每小题4分,共20)

9.当x__________时,分式 <a href="/tags/1/" title="单元" class="c1" target="_blank">单元</a> <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/46/" title="答案" class="c1" target="_blank">答案</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/380/" title="方程" class="c1" target="_blank">方程</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> 有意义;当x__________时,分式 <a href="/tags/1/" title="单元" class="c1" target="_blank">单元</a> <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/46/" title="答案" class="c1" target="_blank">答案</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/380/" title="方程" class="c1" target="_blank">方程</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> 的值为零.

10.根据分式的基本性质,有 <a href="/tags/1/" title="单元" class="c1" target="_blank">单元</a> <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/46/" title="答案" class="c1" target="_blank">答案</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/380/" title="方程" class="c1" target="_blank">方程</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> .

11.若关于x的分式方程 <a href="/tags/1/" title="单元" class="c1" target="_blank">单元</a> <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/46/" title="答案" class="c1" target="_blank">答案</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/380/" title="方程" class="c1" target="_blank">方程</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> 在实数范围内无解,则实数a________.

12.已知 <a href="/tags/1/" title="单元" class="c1" target="_blank">单元</a> <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/46/" title="答案" class="c1" target="_blank">答案</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/380/" title="方程" class="c1" target="_blank">方程</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> ,则 <a href="/tags/1/" title="单元" class="c1" target="_blank">单元</a> <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/46/" title="答案" class="c1" target="_blank">答案</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/380/" title="方程" class="c1" target="_blank">方程</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a>__________.

13.某商店销售一种衬衫,四月份的营业额为5 000元,为扩大销售,五月份将每件衬衫按原价的8折销售,销售量比四月份增加了40件,营业额比四月份增加了600元,求四月份每件衬衫的售价.解决这个问题时,若设四月份的每件衬衫的售价为x元,由题意可列方程为__________

三、解答题(48) 来源:http://www.bcjy123.com/tiku/

14(12)先化简 <a href="/tags/1/" title="单元" class="c1" target="_blank">单元</a> <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/46/" title="答案" class="c1" target="_blank">答案</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/380/" title="方程" class="c1" target="_blank">方程</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> ,然后从-2≤x≤2的范围内选取一个合适的整数作为x的值代入求值.

15.(12)(1)解方程: <a href="/tags/1/" title="单元" class="c1" target="_blank">单元</a> <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/46/" title="答案" class="c1" target="_blank">答案</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/380/" title="方程" class="c1" target="_blank">方程</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a>0

(2)解方程: <a href="/tags/1/" title="单元" class="c1" target="_blank">单元</a> <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/46/" title="答案" class="c1" target="_blank">答案</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/380/" title="方程" class="c1" target="_blank">方程</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> .

16(12)我们把分子为1的分数叫做单位分数,如 <a href="/tags/1/" title="单元" class="c1" target="_blank">单元</a> <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/46/" title="答案" class="c1" target="_blank">答案</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/380/" title="方程" class="c1" target="_blank">方程</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> <a href="/tags/1/" title="单元" class="c1" target="_blank">单元</a> <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/46/" title="答案" class="c1" target="_blank">答案</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/380/" title="方程" class="c1" target="_blank">方程</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> <a href="/tags/1/" title="单元" class="c1" target="_blank">单元</a> <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/46/" title="答案" class="c1" target="_blank">答案</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/380/" title="方程" class="c1" target="_blank">方程</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> ,….任何一个单位分数都可以拆分成两个不同的单位分数的和,如 <a href="/tags/1/" title="单元" class="c1" target="_blank">单元</a> <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/46/" title="答案" class="c1" target="_blank">答案</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/380/" title="方程" class="c1" target="_blank">方程</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> <a href="/tags/1/" title="单元" class="c1" target="_blank">单元</a> <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/46/" title="答案" class="c1" target="_blank">答案</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/380/" title="方程" class="c1" target="_blank">方程</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> <a href="/tags/1/" title="单元" class="c1" target="_blank">单元</a> <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/46/" title="答案" class="c1" target="_blank">答案</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/380/" title="方程" class="c1" target="_blank">方程</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> ,….

(1)根据对上述式子的观察,你会发现 <a href="/tags/1/" title="单元" class="c1" target="_blank">单元</a> <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/46/" title="答案" class="c1" target="_blank">答案</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/380/" title="方程" class="c1" target="_blank">方程</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> .请写出□,○所表示的数.

(2)进一步思考,单位分数 <a href="/tags/1/" title="单元" class="c1" target="_blank">单元</a> <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/46/" title="答案" class="c1" target="_blank">答案</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/380/" title="方程" class="c1" target="_blank">方程</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> (n是不小于2的正整数) <a href="/tags/1/" title="单元" class="c1" target="_blank">单元</a> <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/46/" title="答案" class="c1" target="_blank">答案</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/380/" title="方程" class="c1" target="_blank">方程</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> ,请写出△,☆所表示的代数式,并加以验证.

17(12)甲、乙两同学玩“托球赛跑”游戏,商定:用球拍托着乒乓球从起跑线l起跑,绕过点P跑回到起跑线l(如图所示),途中乒乓球掉下时须捡起并回到掉球处继续赛跑,用时少者胜.结果:甲同学由于心急,掉了球,浪费了6秒钟,乙同学则顺利跑完.事后,乙同学说:“我俩所用的全部时间的和为50秒,捡球过程不算在内时,甲的速度是我的1.2倍.”根据图文信息,请问哪位同学获胜?

 <a href="/tags/1/" title="单元" class="c1" target="_blank">单元</a> <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/46/" title="答案" class="c1" target="_blank">答案</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/380/" title="方程" class="c1" target="_blank">方程</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a>

参考答案

1答案:C

2答案:A

3答案:A

4答案:B

5答案:D

6答案:D

7解析:M <a href="/tags/1/" title="单元" class="c1" target="_blank">单元</a> <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/46/" title="答案" class="c1" target="_blank">答案</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/380/" title="方程" class="c1" target="_blank">方程</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a>N <a href="/tags/1/" title="单元" class="c1" target="_blank">单元</a> <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/46/" title="答案" class="c1" target="_blank">答案</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/380/" title="方程" class="c1" target="_blank">方程</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> ,所以MN.

答案:B

8解析:②③④.注意④中,甲队单独做2天的工作量相当于乙队单独做3天的工作量.

答案:C

9答案:≠-2 =2

10答案:xy x2y2

11答案:1

12答案:1

13答案: <a href="/tags/1/" title="单元" class="c1" target="_blank">单元</a> <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/46/" title="答案" class="c1" target="_blank">答案</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/380/" title="方程" class="c1" target="_blank">方程</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a>

14解:原式= <a href="/tags/1/" title="单元" class="c1" target="_blank">单元</a> <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/46/" title="答案" class="c1" target="_blank">答案</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/380/" title="方程" class="c1" target="_blank">方程</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> .

x满足-2≤x≤2且为整数,若使分式有意义,x只能取0,-2.x0时,原式= <a href="/tags/1/" title="单元" class="c1" target="_blank">单元</a> <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/46/" title="答案" class="c1" target="_blank">答案</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/380/" title="方程" class="c1" target="_blank">方程</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> (或:当x=-2时,原式= <a href="/tags/1/" title="单元" class="c1" target="_blank">单元</a> <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/46/" title="答案" class="c1" target="_blank">答案</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/380/" title="方程" class="c1" target="_blank">方程</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> ). 来源:http://www.bcjy123.com/tiku/

15. 解:(1)方程两边都乘(x1)(x1),得

3(x1)(x3)0

3x3x30

2x0

x0.

检验:将x0代入原方程,得左边=0=右边.

所以x0是原方程的解.

(2)方程两边同乘(x2),得

1=-(1x)3(x2)

解这个方程,得x2.

检验:当x2时,分母x20,所以x2是增根,原方程无解.

16解:(1)□表示的数为6,○表示的数为30

(2)△表示的代数式为n1,☆表示的代数式为n(n1)

 <a href="/tags/1/" title="单元" class="c1" target="_blank">单元</a> <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/46/" title="答案" class="c1" target="_blank">答案</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/380/" title="方程" class="c1" target="_blank">方程</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> .

17解:设乙同学的速度为x/秒,则甲同学的速度为1.2x/秒,根据题意,得

 <a href="/tags/1/" title="单元" class="c1" target="_blank">单元</a> <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/46/" title="答案" class="c1" target="_blank">答案</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/380/" title="方程" class="c1" target="_blank">方程</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> 50,解得x2.5.

经检验,x2.5是原方程的解,且符合题意.

所以甲同学所用的时间为 <a href="/tags/1/" title="单元" class="c1" target="_blank">单元</a> <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/46/" title="答案" class="c1" target="_blank">答案</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/380/" title="方程" class="c1" target="_blank">方程</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a>626()

乙同学所用的时间为 <a href="/tags/1/" title="单元" class="c1" target="_blank">单元</a> <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/46/" title="答案" class="c1" target="_blank">答案</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/380/" title="方程" class="c1" target="_blank">方程</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a>24()

因为2624,所以乙同学获胜.