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【324437】2024春七年级数学下册 第六章 实数综合素质评价(新版)新人教版

时间:2025-01-15 19:35:56 作者: 字数:6849字
简介:


第六章综合素质评价

一、选择题(每题3分,共30)

1.[2023·济宁]实数π0,- <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> 1.5中无理数是(  )

A.π B.0 C. <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> D.1.5

2.如果实数m没有平方根,那么m可以是(  )

A.32 B.|-3 C.(3)2 D.(3)

3.对于无理数 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> ,添加关联的数或者运算符号组成新的式子,其运算结果能成为有理数的是(  )

A.2 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> 3 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> B. <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> C.( <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> )3 D.0× <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a>

4. <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> 下列判断正确的是(  )

A.0 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> 1 B.1 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> 2 C.2 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> 3 D.3 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> 4

5.已知|a1|+|b4|=0,则 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> 的平方根是(  )

A. <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> B.± <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> C.± <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> D. <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a>

6.某数的两个不同的平方根为2a1与-a2,则这个数是(  )

A.1 B.3 C.3 D.9

7.[2022·临沂]如图,AB位于数轴上原点两侧,且OB2OA,若点B表示的数是6,则点A表示的数是(  )

 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a>

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

8. <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> 如图,输入m <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> ,则输出的数为(  )

 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a>

A.8 B.16 C.32 D.64

9.一个正方体木块的体积是343 cm3,现将它锯成8个同样大小的小正方体木块,则每个小正方体木块的表面积是(  )

A. <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> cm2 B. <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> cm2 C. <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> cm2 D. <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> cm2

10.[2023·北大附中期中]如图,用边长为3的两个小正方形拼成一个大正方形,则大正方形的边长最接近的整数是(  )

 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a>

A.3 B.4 C.5 D.6

二、填空题(每题3分,共24)

11. <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> 请写出一个比 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> 小的整数:    .

12. <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> 2的相反数是    .

13.已知m <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> 的整数部分,n <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> 的小数部分,则mn    .

14. <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> 0,则(x1)2(y3)2    .

15.一个正数x的平方根分别是3a416a,则x的值是    .

16.若实数ab互为相反数,cd互为倒数,则- <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a>     .

17.(母题:教材P54探究)如图,在数轴上竖直摆放一个直径为4个单位长度的半圆形,A是半圆的中点,半圆形直径的一个端点位于原点O.该半圆形沿数轴从原点O开始向右无滑动滚动,当点A第一次落在数轴上时,此时点A表示的数为    .

 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a>

(17)

18. <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> 现有两个大小不等的正方体茶叶罐,大正方体茶叶罐的体积为1 000 cm3,小正方体茶叶罐的体积为125 cm3,将其叠放在一起放在地面上(如图),则这两个茶叶罐的最高点A到地面的距离是    cm.

 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a>

(18)

三、解答题(1916分,2018分,216分,227分,239分,2410分,共66)

19.(母题:教材P61复习题T8)计算:

(1)(1)3+|1 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> |+ <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> (2)3 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> 5 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> 4 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a>




(3)3( <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> )2( <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> ) (4)(1)2 024 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> 3 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> × <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> .




20.(母题:教材P61复习题T9)求下列各式中未知数的值:

(1)a2|= <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> (2)4x225




(3)(x0.7)30.027.




21.已知abc在数轴上对应点的位置如图所示,化简: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> .

 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a>




22.[2023·人大附中月考]已知2既是a5的一个平方根,也是7a2b1的立方根,解关于x的方程:a(x2)29b0.





23.我们知道 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> 是无理数,其整数部分是1,于是小明用 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> 1来表示 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> 的小数部分.请解答:

(1)如果 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> 的小数部分为a <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> 2的整数部分为b,求ab <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> 的值;

(2)已知10 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> xy,其中x是整数,且0y1,求xy的相反数.




24.(母题:教材P433)勤俭节约是中国人民的传统美德.涛涛的爷爷是能工巧匠,他把两张正方形桌面重新拼成一张大正方形桌面,其面积为169 dm2,已知他用的两张正方形桌面,其中一张的边长为5 dm,那么另一张桌面的边长应为多少才能拼出面积为169 dm2的桌面?





答案

一、1.A

2.A 【点拨】利用乘方、绝对值的性质及去括号法则逐一化简各选项,根据只有非负数有平方根,负数没有平方根即可得到答案.

3.D 4.B 5.B 6.D 7.B

8.B 【点拨】输入m <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> ,可得( <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> )2810

 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> 4421610,∴输出16,故选B.

9.D 【点拨】由题意可知,每个小正方体木块的体积为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> cm3,则每个小正方体木块的棱长为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> cm,故每个小正方体木块的表面积为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> ×6 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> (cm2).

10.B 【点拨】大正方形的边长为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> .

161825

 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> ,即4 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> 5.

又∵5 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> ( <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> 4)

5 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> 4

92 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a>

2×(4.5 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> )

2×( <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> )0

5 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> 4

 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> 最接近的整数是4

即大正方形的边长最接近的整数是4.

二、11.4(答案不唯一)

12.2 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a>

13.5 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a>  【点拨】∵2 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> 3,∴m2.∵3 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> 4,∴n <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> 3,∴mn2( <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> 3)5 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> .

14.25 【点拨】由题意得,x10y20,解得x1y2,则(x1)2(y3)2(11)2(23)225.

15.49 【点拨】由题意得3a416a0,解得a=-1,所以正数x的平方根是7和-7.故正数x的值是49.

16.1 【点拨】因为实数ab互为相反数,cd互为倒数,所以ab0cd1,所以- <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> 011.

17.4π 18.15

三、19.【解】(1)原式=-1 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> 12 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> .

(2)原式=(354) <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> 4 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> .

(3)原式=3 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> 3 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> 2 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> 2 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> 5 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> .

(4)原式=12311.

 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> 实数的运算顺序:先算乘方、开方,再算乘、除,最后算加、减,如果没有括号,在同一级运算中要从左到右依次运算,有括号的先算括号里的.无论何种运算,都要注意先定符号再运算.

20.【解】(1)由|a2|= <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a>

a2 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> a2=- <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> .

a2 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> 时,a <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> 2

a2=- <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> 时,a=- <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> 2.

(2)因为4x225

所以x2 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> .所以x± <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> .

(3)因为(x0.7)30.027

所以x0.70.3.所以x1.

21.【解】由数轴可知ba0c

所以ab0ca0bc0.

所以原式=-a[(ab)](ca)[(bc)]=-aabcabc=-a2c.

22.【解】∵2既是a5的一个平方根,也是7a2b1的立方根,

a52247a2b1238.

a=-1b=-7.

方程为-(x2)2630.

(x2)263.

x2± <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> .

x2 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> x2 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> .

23.【解】(1)因为2 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> 3 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> 的小数部分为a

所以a <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> 2.

因为3 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> 4,所以5 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> 26.

因为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> 2的整数部分为b,所以b5

所以ab <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> 25 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> 3.

(2)因为2 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> 310 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> xy,其中x是整数,0y1

所以x10212y10 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> 12 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> 2.

所以xy12( <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> 2)14 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> .

所以xy的相反数是-14 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/279/" title="综合" class="c1" target="_blank">综合</a> <a href="/tags/300/" title="素质" class="c1" target="_blank">素质</a> <a href="/tags/499/" title="评价" class="c1" target="_blank">评价</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> .

24.【解】设另一张桌面的边长为xdm,则有x252169

所以x216925144.

因为144的算术平方根是12,所以x12.

答:另一张桌面的边长应为12 dm才能拼出面积为169 dm2的桌面.


Shape2

7

7