当前位置:首页 > 八年级 > 数学试卷

【329528】2.3 立方根 课堂练习

时间:2025-01-21 13:16:12 作者: 字数:1313字
简介:


 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/909/" title="立方根" class="c1" target="_blank">立方根</a> <a href="/tags/937/" title="课堂" class="c1" target="_blank">课堂</a>

2.3 立方根

.判断题

(1)如果ba的三次幂,那么b的立方根是a.( )

(2)任何正数都有两个立方根,它们互为相反数.( )

(3)负数没有立方根.( )

(4)如果ab的立方根,那么ab≥0.( )

.填空题

(1)如果一个数的立方根等于它本身,那么这个数是________.

(2) <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/909/" title="立方根" class="c1" target="_blank">立方根</a> <a href="/tags/937/" title="课堂" class="c1" target="_blank">课堂</a> =________( <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/909/" title="立方根" class="c1" target="_blank">立方根</a> <a href="/tags/937/" title="课堂" class="c1" target="_blank">课堂</a> )3=________

(3) <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/909/" title="立方根" class="c1" target="_blank">立方根</a> <a href="/tags/937/" title="课堂" class="c1" target="_blank">课堂</a> 的平方根是________.

(4) <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/909/" title="立方根" class="c1" target="_blank">立方根</a> <a href="/tags/937/" title="课堂" class="c1" target="_blank">课堂</a> 的立方根是________.

.选择题

(1)如果a(3)2的平方根,那么 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/909/" title="立方根" class="c1" target="_blank">立方根</a> <a href="/tags/937/" title="课堂" class="c1" target="_blank">课堂</a> 等于( )

A.3 B. <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/909/" title="立方根" class="c1" target="_blank">立方根</a> <a href="/tags/937/" title="课堂" class="c1" target="_blank">课堂</a> C.±3 D. <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/909/" title="立方根" class="c1" target="_blank">立方根</a> <a href="/tags/937/" title="课堂" class="c1" target="_blank">课堂</a> 或- <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/909/" title="立方根" class="c1" target="_blank">立方根</a> <a href="/tags/937/" title="课堂" class="c1" target="_blank">课堂</a>

(2)x0,则 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/909/" title="立方根" class="c1" target="_blank">立方根</a> <a href="/tags/937/" title="课堂" class="c1" target="_blank">课堂</a> 等于( )

A.x B.2x C.0 D.2x

(3)a2=(5)2,b3=(5)3,a+b的值为( )

A.0 B.±10 C.010 D.0或-10

  1. 如图:数轴上点A表示的数为x,则x213的立方根是( )

 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/909/" title="立方根" class="c1" target="_blank">立方根</a> <a href="/tags/937/" title="课堂" class="c1" target="_blank">课堂</a>

A. <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/909/" title="立方根" class="c1" target="_blank">立方根</a> <a href="/tags/937/" title="课堂" class="c1" target="_blank">课堂</a> 13 B. <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/909/" title="立方根" class="c1" target="_blank">立方根</a> <a href="/tags/937/" title="课堂" class="c1" target="_blank">课堂</a>13 C.2 D.2

(5)如果2(x2)3=6 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/909/" title="立方根" class="c1" target="_blank">立方根</a> <a href="/tags/937/" title="课堂" class="c1" target="_blank">课堂</a> ,x等于( )

A. <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/909/" title="立方根" class="c1" target="_blank">立方根</a> <a href="/tags/937/" title="课堂" class="c1" target="_blank">课堂</a> B. <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/909/" title="立方根" class="c1" target="_blank">立方根</a> <a href="/tags/937/" title="课堂" class="c1" target="_blank">课堂</a> C. <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/909/" title="立方根" class="c1" target="_blank">立方根</a> <a href="/tags/937/" title="课堂" class="c1" target="_blank">课堂</a>  <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/909/" title="立方根" class="c1" target="_blank">立方根</a> <a href="/tags/937/" title="课堂" class="c1" target="_blank">课堂</a> D.以上答案都不对

.若球的半径为R,则球的体积VR的关系式为V= <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/909/" title="立方根" class="c1" target="_blank">立方根</a> <a href="/tags/937/" title="课堂" class="c1" target="_blank">课堂</a> πR3.已知一个足球的体积为6280 cm3,试计算足球的半径.(π3.14,精确到0.1)

参考答案

.(1)√ (2)× (3)× (4)√

.(1)0±1 (2) <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/909/" title="立方根" class="c1" target="_blank">立方根</a> <a href="/tags/937/" title="课堂" class="c1" target="_blank">课堂</a> 8 (3)±2 (4)2

.(1)D (2)D (3)D (4)D (5)B

.解:由已知6280= <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/909/" title="立方根" class="c1" target="_blank">立方根</a> <a href="/tags/937/" title="课堂" class="c1" target="_blank">课堂</a> π·R3

∴6280≈ <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/909/" title="立方根" class="c1" target="_blank">立方根</a> <a href="/tags/937/" title="课堂" class="c1" target="_blank">课堂</a> ×3.14R3,∴R3=1500,∴R≈11.3 cm