人教版数学七年级上册期中复习试卷05（含答案）

人教版数学七年级上册期中复习试卷 

一、选择题：

1．－2的相反数是(        )

A．－2    B．2    C．    D．

2．单项式的系数是(        )

A．    B．π    C．2    D．

3．计算－42＝(        )

A．－8    B．－16    C．16    D．8

4．下列计算正确的是(        )

A．x2＋x2＝x4  B．x2＋x3＝2x5  C．3x－2x＝1  D．x2y－2x2y＝－x2y

5．地球上的陆地面积约为149000000平方千米，这个数字用科学记数法表示应为 (    )

A．0.149×106  B．1.49×107      C．1.49×108      D．14.9×107

6．一个整式减去－等于＋则这个整式为(        )

A．2b2    B．2a2    C．－2b2       D．－2a2

7．当x＝－1时，代数式x2＋2x＋1的值是(        )

A．－2    B．－1    C．0    D．4

8．数x、y在数轴上对应点如图所示，则化简|x＋y|－|y－x|的结果是(        )

A．0    B．2x    C．2y    D．2x－2y

9．计算(－3)×÷(－)×3的结果是(        )

A.－9    B. 9    C.1        D.－1

10．已知4n－m＝4，则(m－4n)2－3(m－4n)－10 的值是(        )

A.－6    B.6     C.18   D.－38

二、填空题：

11．在数轴上将点A向右移动7个单位，再向左移动4个单位，终点恰好是原点，则点A表示的数是      ．

12．计算：|1－3|＝          ．

13．已知2xayb与－7xb－3y4是同类项，则ab＝           ．

14．比较大小：①0      －0.5，          ②－      － (用“＞”或“＜”填写)

15．－5x2y2＋3x2y＋2x－5是      次四项式．

16．4.6495精确到0.001的近似数是      ．

17．已知当x＝1时，代数式ax3＋bx＋5的值为－9，那么当x＝－1时，代数式ax3＋bx＋5的值为__________．

18．观察一列单项式：a，－2a2，4a3，－8a4…根据你发现的规律，第7个单项式为      ；第n个单项式为      ．

三、解答题

19．(6分)计算：

(1) －3＋5.3＋7－5.3     (2) 0.35＋(－0.6)＋0.25＋(－5.4)

20．(6分)计算：

(1) 3×(－4)＋18÷(－6)   (2) (－2)2×5＋(－2)3÷4．

21．(6分)化简：

(1) x2y－3xy2＋2yx2－y2x          (2)（－ab＋2a)－(3a－ab)；

22．(6分)出租车司机小李某天上午从家出发，营运时是在东西走向的大街上进行的，如果规定向东为正，向西为负，他这天上午所接六位乘客的行车里程(单位：km)如下：－1，＋6，－2，＋2，－7，－4．

(1)将最后一位乘客送到目的地时，小李在出发地的哪一边？距离出发地多少km？

(2)若汽车每千米耗油量为0.2升，这天上午小李接送乘客，出租车共耗油多少升？

23．(5分)先化简，再求值：(2x2＋x)－［4x2－(3x2－x)］,其中x＝－．

24．(8分)计算：

(1) (－＋)×(－36)         (2) －42－6×＋2×(－1)÷(－) 

25(7分)．挑战自我！下图是由一些火柴棒搭成的图案：

(1)摆第①个图案用      根火柴棒，

摆第②个图案用      根火柴棒，

摆第③个图案用      根火柴棒．

(2)按照这种方式摆下去，摆第n个图案用多少根火柴棒？

(3)计算一下摆121根火柴棒时，是第几个图案？

26．(6分)若a，b互为相反数，c，d互为倒数，m的绝对值是1，n是有理数且既不是正数也不是负数，求20161－(a＋b)＋m2              －(cd)2016＋n(a＋b＋c＋d)的值．

27．(7分)如图，一只甲虫在5×5的方格(每小格边长为1)上沿着网格线运动，它从A处出发看望B、C、D处的其它甲虫．规定：向上向右走为正，向下向左走为负，如果从A到B记为：A→B(＋1，＋4)，从B到A记为：B→A(－1，－4)．其中第一数表示左右方向，第二个数表示上下方向，那么图中

(1)A→C(      ，      )，B→D(      ，      )；

(2)若这只甲虫的行走路线为A→B→C→D，请计算该甲虫走过的路程．

28．(9分)同学们都知道：|5－(－2)|表示5与－2之差的绝对值，实际上也可理解为5与－2两数在数轴上所对应的两点之间的距离．请你借助数轴进行以下探索：

(1)数轴上表示5与－2两点之间的距离是      ，

(2)数轴上表示x与2的两点之间的距离可以表示为      ．

(3)如果|x－2|＝5，则x＝      ．

(4)同理|x＋3|＋|x－1|表示数轴上有理数x所对应的点到－3和1所对应的点的距离之和，请你找出所有符合条件的整数x，使得|x＋3|＋|x－1|＝4，这样的整数是      ．

(5)由以上探索猜想对于任何有理数x，|x－3|＋|x－6|是否有最小值？如果有，直接写出最小值；如果没有，说明理由．

数学试卷参考答案及评分标准

一、选择题：本大题共10小题，每小题3分，共30分.

二、填空题：本大题共8小题，每小题4分，共32分.

   11．－3  12．2         13．1         14．＞、＞   

   15．四   16．4.650    17．19         18．(－2)n－1an

三、解答题（一）：本大题共5小题，共38分.

19．(6分)

(1)－3＋5.3＋7－5.3

＝－3＋7····························································2分

＝4；································································                                                        3分

(2)0.35＋(－0.6)＋0.25＋(－5.4)

＝0.35＋0.25＋(－0.6)＋(－5.4)········································4分

＝0.6＋(－6)························································5分

＝－5.4；···························································6分

20．(6分)

(1)3×(－4)＋18÷(－6)

＝－12＋(－3)·······················································2分

＝－15；····························································3分

(2)(－2)2×5＋(－2)3÷4

＝4×5＋(－8)÷4·····················································4分

＝20＋(－2)·························································5分

＝18．·····························································6分

21．(6分)

(1)原式＝x2y＋2x2y－3xy2－xy2 ········································2分

＝3x2y－4xy2························································3分

(2) (－ab＋2a)－(3a－ab)

＝－ab＋2a－3a＋ab···················································5分

＝－a······························································6分

22．(6分)

解：(1)(－1)＋6＋(－2)＋2＋(－7)＋(－4)＝－6，···························2分

答：将最后一位乘客送到目的地时，小李在出发地的西边，距离出发地6km处；······3分

(2))(|－1|＋6＋|－2|＋2＋|－7|＋|－4|)×0.2＝22×0.2＝4.4(升)，············5分

答：这天上午小李接送乘客，出租车共耗油4.4升．···························6分

23．(5分)

(2x2＋x)－[4x2－(3x2－x)]

＝2x2＋x－[4x2－3x2＋x]···············································2分

＝2x2＋x－4x2＋3x2－x················································3分

＝x2，·····························································4分

当x＝－时，原式＝(－)2＝．············································5分

四、解答题（二）：本大题共5小题，共50分.

24．(8分)

（1）(－＋)×(－36)

＝－20＋27－2·······················································3分

＝5································································4分

（2）－42－6×＋2×(－1)÷(－)

＝－16－8＋4························································7分

＝32·······························································8分

25．(7分)

第②个图案所用的火柴数： 9，··········································1分

第③个图案所用的火柴数： 13，·········································2分

(2)按(1)的方法，依此类推，

由规律可知5＝4×1＋1，9＝4×2＋1，13＝4×3＋1，

第n个图案中，所用的火柴数为：1＋4＋4＋…＋4＝1＋4×n＝4n＋1；·············5分

故摆第n个图案用的火柴棒是4n＋1；

(3)根据规律可知4n＋1＝121得，n＝30．···································7分

26．(6分)

解：∵a，b互为相反数，c，d互为倒数，m的绝对值是1，n是有理数且既不是正数也不是负数，

∴a＋b＝0，cd＝1，m＝±1，n＝0，·······································3分

∴20161－(a＋b)＋m2－(cd)2016＋n(a＋b＋c＋d)

＝2016＋1－1＋0······················································5分

＝2016．····························································6分

27．(7分)

解：(1)∵规定：向上向右走为正，向下向左走为负，

∴A→C记为(＋3，＋4)；B→D记为(＋3，－2)；

故答案为：＋3，＋4，＋3，－2；········································4分

(2)据已知条件可知：A→B表示为：(1，4)，B→C记为(2，0)C→D记为(1，－2)；

故该甲虫走过的路线长为1＋4＋2＋1＋2＝10．·······························7分

28．(9分)

解：(1) 7；·························································1分

(2) |x－2|；························································2分

(3) 7或－3；························································4分

(4)∵|x＋3|＋|x－1|表示数轴上有理数x所对应的点到－3和1所对应的点的距离之和，|x＋3|＋|x－1|＝4，

∴这样的整数有－3、－2、－1、0、1，····································7分

故答案为：－3、－2、－1、0、1；

(5)有最小值是3．·····················································9分