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【323354】2023八年级数学上册 第二章 实数2.3 立方根同步练习(新版)北师大版

时间:2025-01-15 20:34:44 作者: 字数:1977字
简介:


2.3 立方根

 

一、选择题

1.﹣8的立方根是(  )

A.﹣2 B±2 C2 D.﹣ <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> <a href="/tags/909/" title="立方根" class="c1" target="_blank">立方根</a>  <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> <a href="/tags/909/" title="立方根" class="c1" target="_blank">立方根</a>

2.若一个数的立方根是﹣3,则该数为(  )

A <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> <a href="/tags/909/" title="立方根" class="c1" target="_blank">立方根</a>  <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> <a href="/tags/909/" title="立方根" class="c1" target="_blank">立方根</a> B.﹣27 C± <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> <a href="/tags/909/" title="立方根" class="c1" target="_blank">立方根</a>  <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> <a href="/tags/909/" title="立方根" class="c1" target="_blank">立方根</a> D±27

3.有如下命题:

负数没有立方根;

一个实数的立方根不是正数就是负数;

一个正数或负数的立方根与这个数同号;

如果一个数的立方根是这个数本身,那么这个数是10

其中错误的是(  )

A.①②③ B.①②④ C.②③④ D.①③④

4.下列计算正确的是(  )

A <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> <a href="/tags/909/" title="立方根" class="c1" target="_blank">立方根</a>  <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> <a href="/tags/909/" title="立方根" class="c1" target="_blank">立方根</a> B <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> <a href="/tags/909/" title="立方根" class="c1" target="_blank">立方根</a>  <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> <a href="/tags/909/" title="立方根" class="c1" target="_blank">立方根</a> C <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> <a href="/tags/909/" title="立方根" class="c1" target="_blank">立方根</a>  <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> <a href="/tags/909/" title="立方根" class="c1" target="_blank">立方根</a> D <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> <a href="/tags/909/" title="立方根" class="c1" target="_blank">立方根</a>  <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> <a href="/tags/909/" title="立方根" class="c1" target="_blank">立方根</a>

 

二、填空题

5 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> <a href="/tags/909/" title="立方根" class="c1" target="_blank">立方根</a>  <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> <a href="/tags/909/" title="立方根" class="c1" target="_blank">立方根</a> 的立方根是______

6.若一个数的平方根为±8,则这个数的立方根为______

7.一个正方体的体积为125cm3,则这个正方体的表面积为______cm2

 

三、解答题

8.求下列各数的立方根

1729 2)﹣4 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> <a href="/tags/909/" title="立方根" class="c1" target="_blank">立方根</a>  <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> <a href="/tags/909/" title="立方根" class="c1" target="_blank">立方根</a> 3)﹣ <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> <a href="/tags/909/" title="立方根" class="c1" target="_blank">立方根</a>  <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> <a href="/tags/909/" title="立方根" class="c1" target="_blank">立方根</a>4)(﹣53

9.求下列各式的值:

1 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> <a href="/tags/909/" title="立方根" class="c1" target="_blank">立方根</a>  <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> <a href="/tags/909/" title="立方根" class="c1" target="_blank">立方根</a>2)( <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> <a href="/tags/909/" title="立方根" class="c1" target="_blank">立方根</a>  <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> <a href="/tags/909/" title="立方根" class="c1" target="_blank">立方根</a>3

10.求下列各式中的x

18x3+27=0





264x+13=27




11.已知第一个正方体纸盒的棱长为6cm,第二个正方体纸盒的体积比第一个纸盒的体积大127cm3,求第二个纸盒的棱长.









12.我们知道a+b=0时,a3+b3=0也成立,若将a看成a3的立方根,b看成b3的立方根,我们能否得出这样的结论:若两个数的立方根互为相反数,则这两个数也互为相反数.

1)试举一个例子来判断上述猜测结论是否成立;

2)若 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> <a href="/tags/909/" title="立方根" class="c1" target="_blank">立方根</a>  <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> <a href="/tags/909/" title="立方根" class="c1" target="_blank">立方根</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> <a href="/tags/909/" title="立方根" class="c1" target="_blank">立方根</a>  <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> <a href="/tags/909/" title="立方根" class="c1" target="_blank">立方根</a> 互为相反数,求1﹣ <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> <a href="/tags/909/" title="立方根" class="c1" target="_blank">立方根</a>  <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> <a href="/tags/909/" title="立方根" class="c1" target="_blank">立方根</a> 的值.

 

答案

 

一、选择题

1A2B3B4C; 

二、填空题

5 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> <a href="/tags/909/" title="立方根" class="c1" target="_blank">立方根</a>  <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> <a href="/tags/909/" title="立方根" class="c1" target="_blank">立方根</a>647150

三、解答题

8.(1) 9 ;(2- 5/3 ;(3- 5/6;(4-125

9.(1-27;(264

10.(1- 3/2 2- 1/4

117 cm 12.(1)成立;(2-1

3