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【329300】《分式》单元测试2

时间:2025-01-21 12:53:56 作者: 字数:3385字
简介:

3章 分式

一、选择题(每小题3分,共30分)

1.在下列各式 <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/846/" title="分式" class="c1" target="_blank">分式</a> 中,是分式的有( )

A.2B.3C.4D.5

2.要使分式 <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/846/" title="分式" class="c1" target="_blank">分式</a> 有意义,则x的取值范围是( )

A.x= <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/846/" title="分式" class="c1" target="_blank">分式</a> B.x> <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/846/" title="分式" class="c1" target="_blank">分式</a> C.x< <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/846/" title="分式" class="c1" target="_blank">分式</a> D.x <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/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/846/" title="分式" class="c1" target="_blank">分式</a>

3.若分式 <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/846/" title="分式" class="c1" target="_blank">分式</a> 的值为零,则x等于( )

A.2 B.-2 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/846/" title="分式" class="c1" target="_blank">分式</a> D.0

4.如果分式 <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/846/" title="分式" class="c1" target="_blank">分式</a> 的值为正整数,则整数x的值的个数是( )

A.2B.3C.4D.5

5.有游客m人,若果每n个人住一个房间,结果还有一个人无房住,这客房的间数为( )

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/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/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/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/846/" title="分式" class="c1" target="_blank">分式</a>

6.a千克盐溶于b千克水中,得到一种盐水,若有这种盐水x千克,则其中含盐( )

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/846/" title="分式" class="c1" target="_blank">分式</a> 千克 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/846/" title="分式" class="c1" target="_blank">分式</a> 千克 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/846/" title="分式" class="c1" target="_blank">分式</a> 千克 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/846/" title="分式" class="c1" target="_blank">分式</a> 千克

7.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/846/" title="分式" class="c1" target="_blank">分式</a> 所得的正确结论为( )

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/846/" title="分式" class="c1" target="_blank">分式</a> B.1 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/846/" title="分式" class="c1" target="_blank">分式</a> D.-1

8.把分式 <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/846/" title="分式" class="c1" target="_blank">分式</a> 化简的正确结果为( )

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/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/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/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/846/" title="分式" class="c1" target="_blank">分式</a>

9.x= <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/846/" title="分式" class="c1" target="_blank">分式</a> 时,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/846/" title="分式" class="c1" target="_blank">分式</a> 的值是( )

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/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/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/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/846/" title="分式" class="c1" target="_blank">分式</a>

10.某工地调来72人参加挖土和运土,已知3人挖出的土1人恰好能全部运走.怎样调配劳动力才能使挖出的土能及时运走且不窝工.解决此问题,可设派x人挖土,其他人运土,列方程为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/846/" title="分式" class="c1" target="_blank">分式</a>72-x= <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/846/" title="分式" class="c1" target="_blank">分式</a> ③x+3x=72④ <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/846/" title="分式" class="c1" target="_blank">分式</a> 上述所列方程正确的有( )

A.1B.2C.3D.4



二、填空题(每小题3分,共30分)

11.若分式 <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/846/" title="分式" class="c1" target="_blank">分式</a> 的值为0,则a= .

12.已知当x=-2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/846/" title="分式" class="c1" target="_blank">分式</a> 无意义,x=4时,此分式的值为0,则a+b= .

13.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/846/" title="分式" class="c1" target="_blank">分式</a>x的代数式表示y .

14.化简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/846/" title="分式" class="c1" target="_blank">分式</a> .

15.使分式方程 <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/846/" title="分式" class="c1" target="_blank">分式</a> 产生增根,m的值为 .

16.要使 <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/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/846/" title="分式" class="c1" target="_blank">分式</a> 的值相等,则x= .

17.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/846/" title="分式" class="c1" target="_blank">分式</a> .

18.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/846/" title="分式" class="c1" target="_blank">分式</a> ,则ab= .

19. <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/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/846/" title="分式" class="c1" target="_blank">分式</a> 互为倒数,则x= .

20.汛期将至,我军机械化工兵连的官兵为驻地群众办实事,计划加固驻地附近20千米的河堤.根据气象部门预测,今年的汛期有可能提前,因此官兵们发扬我军不怕苦,不怕累的优良传统,找出晚归,使实际施工速度提高到计划的1.5倍,结果比计划提前10天完成,问该连实际每天加固河堤多少千米?列方程解此应用题时,若计划每天加固河堤x千米,则实际每天加固1.5x千米,根据题意可列方程为 .



三、解答题(共60分)

21.7分)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/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/846/" title="分式" class="c1" target="_blank">分式</a> ;



22.7分)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/846/" title="分式" class="c1" target="_blank">分式</a> ;



23.8分)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/846/" title="分式" class="c1" target="_blank">分式</a> .




24.8分)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/846/" title="分式" class="c1" target="_blank">分式</a> ;



25.10分)已知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/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/846/" title="分式" class="c1" target="_blank">分式</a> 得值.



26.10分)若关于x的方程 <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/846/" title="分式" class="c1" target="_blank">分式</a> 有增根,试求k的值.



27.10分)A,B两地相距80千米,一辆公共汽车从A地出发开往B地,2小时后,又从A地开来一辆小汽车,小汽车的速度是公共汽车的3.结果小汽车比公共汽车早到40分钟到达B.求两种车的速度.




参考答案

1.B 2.D 3.B 4.C 5.A 6.A 7.C 8.A 9.A 10.C

11.-2 12.2 13.y= <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/846/" title="分式" class="c1" target="_blank">分式</a>

14. <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/846/" title="分式" class="c1" target="_blank">分式</a> 15. <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/846/" title="分式" class="c1" target="_blank">分式</a> 16.6 17.1 18. <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/846/" title="分式" class="c1" target="_blank">分式</a> 19. <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/846/" title="分式" class="c1" target="_blank">分式</a> 20. <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/846/" title="分式" class="c1" target="_blank">分式</a>

21.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/846/" title="分式" class="c1" target="_blank">分式</a>

22.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/846/" title="分式" class="c1" target="_blank">分式</a>

23.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/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/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/846/" title="分式" class="c1" target="_blank">分式</a>

24.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/846/" title="分式" class="c1" target="_blank">分式</a>

25.a+b=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/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/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/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/846/" title="分式" class="c1" target="_blank">分式</a>

26.方程可化为k+2(x-3)=4-x,由题意知x=3,k=1

27.设公共汽车的速度为x千米/小时,则小汽车的速度为3x千米/小时,

由题意可列方程为

 <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/846/" title="分式" class="c1" target="_blank">分式</a> 解得x=20.

经检验x=20适合题意,

3x=60

即公共汽车的速度为20千米/小时,小汽车的速度为60千米/小时.