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【329504】2.2 平方根 课堂练习2

时间:2025-01-21 13:14:59 作者: 字数:3338字
简介:


 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/61/" title="平方" class="c1" target="_blank">平方</a> <a href="/tags/908/" title="平方根" class="c1" target="_blank">平方根</a> <a href="/tags/937/" title="课堂" class="c1" target="_blank">课堂</a>

2.2 平方根

一、选择题

1)下列说法正确的是( )个

 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/61/" title="平方" class="c1" target="_blank">平方</a> <a href="/tags/908/" title="平方根" class="c1" target="_blank">平方根</a> <a href="/tags/937/" title="课堂" class="c1" target="_blank">课堂</a> 的平方根是 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/61/" title="平方" class="c1" target="_blank">平方</a> <a href="/tags/908/" title="平方根" class="c1" target="_blank">平方根</a> <a href="/tags/937/" title="课堂" class="c1" target="_blank">课堂</a>

-9的算方平方根是+3

 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/61/" title="平方" class="c1" target="_blank">平方</a> <a href="/tags/908/" title="平方根" class="c1" target="_blank">平方根</a> <a href="/tags/937/" title="课堂" class="c1" target="_blank">课堂</a> 的平方根是 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/61/" title="平方" class="c1" target="_blank">平方</a> <a href="/tags/908/" title="平方根" class="c1" target="_blank">平方根</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/61/" title="平方" class="c1" target="_blank">平方</a> <a href="/tags/908/" title="平方根" class="c1" target="_blank">平方根</a> <a href="/tags/937/" title="课堂" class="c1" target="_blank">课堂</a> 11的算术平方根;

36的平方根是-6

A1 B2 C3 D0

2)若 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/61/" title="平方" class="c1" target="_blank">平方</a> <a href="/tags/908/" title="平方根" class="c1" target="_blank">平方根</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/61/" title="平方" class="c1" target="_blank">平方</a> <a href="/tags/908/" title="平方根" class="c1" target="_blank">平方根</a> <a href="/tags/937/" title="课堂" class="c1" target="_blank">课堂</a> ,则 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/61/" title="平方" class="c1" target="_blank">平方</a> <a href="/tags/908/" title="平方根" class="c1" target="_blank">平方根</a> <a href="/tags/937/" title="课堂" class="c1" target="_blank">课堂</a> 的值等于( )

A1 B2 C10 D <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/61/" title="平方" class="c1" target="_blank">平方</a> <a href="/tags/908/" title="平方根" class="c1" target="_blank">平方根</a> <a href="/tags/937/" title="课堂" class="c1" target="_blank">课堂</a>

3)若 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/61/" title="平方" class="c1" target="_blank">平方</a> <a href="/tags/908/" title="平方根" class="c1" target="_blank">平方根</a> <a href="/tags/937/" title="课堂" class="c1" target="_blank">课堂</a> ,则x为( )

A1-5 B-15

C15 D-1-5

4)设 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/61/" title="平方" class="c1" target="_blank">平方</a> <a href="/tags/908/" title="平方根" class="c1" target="_blank">平方根</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/61/" title="平方" class="c1" target="_blank">平方</a> <a href="/tags/908/" title="平方根" class="c1" target="_blank">平方根</a> <a href="/tags/937/" title="课堂" class="c1" target="_blank">课堂</a> ,则xy的值为( )

A5 B-5 C25 D-25

5)设x16的平方根, <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/61/" title="平方" class="c1" target="_blank">平方</a> <a href="/tags/908/" title="平方根" class="c1" target="_blank">平方根</a> <a href="/tags/937/" title="课堂" class="c1" target="_blank">课堂</a> ,则xy的关系是( )

A <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/61/" title="平方" class="c1" target="_blank">平方</a> <a href="/tags/908/" title="平方根" class="c1" target="_blank">平方根</a> <a href="/tags/937/" title="课堂" class="c1" target="_blank">课堂</a> Bx=y

Cx=-y D <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/61/" title="平方" class="c1" target="_blank">平方</a> <a href="/tags/908/" title="平方根" class="c1" target="_blank">平方根</a> <a href="/tags/937/" title="课堂" class="c1" target="_blank">课堂</a>

6)若 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/61/" title="平方" class="c1" target="_blank">平方</a> <a href="/tags/908/" title="平方根" class="c1" target="_blank">平方根</a> <a href="/tags/937/" title="课堂" class="c1" target="_blank">课堂</a> ,则a+b值为( )

A0 B2

C0-2 D02


二、判断题

1100的平方根是10.( )

2.-981的平方根.( )

3.-9没有平方根.( )

4.任何数如果有平方根,那么一定有两个不同的平方根,这两个平方根互为相反数.( )

5.-1的平方根是-1.( )

6. 若 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/61/" title="平方" class="c1" target="_blank">平方</a> <a href="/tags/908/" title="平方根" class="c1" target="_blank">平方根</a> <a href="/tags/937/" title="课堂" class="c1" target="_blank">课堂</a> ( )

三、解答题

1.填表。其中 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/61/" title="平方" class="c1" target="_blank">平方</a> <a href="/tags/908/" title="平方根" class="c1" target="_blank">平方根</a> <a href="/tags/937/" title="课堂" class="c1" target="_blank">课堂</a>

a



13

14


16

17


19


 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/61/" title="平方" class="c1" target="_blank">平方</a> <a href="/tags/908/" title="平方根" class="c1" target="_blank">平方根</a> <a href="/tags/937/" title="课堂" class="c1" target="_blank">课堂</a>

121

144



225



324


400

2.求下列各数的平方根及算术平方根:169361 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/61/" title="平方" class="c1" target="_blank">平方</a> <a href="/tags/908/" title="平方根" class="c1" target="_blank">平方根</a> <a href="/tags/937/" title="课堂" class="c1" target="_blank">课堂</a>00.360.0121 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/61/" title="平方" class="c1" target="_blank">平方</a> <a href="/tags/908/" title="平方根" class="c1" target="_blank">平方根</a> <a href="/tags/937/" title="课堂" class="c1" target="_blank">课堂</a>9001937

3.求下列各式的值:

 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/61/" title="平方" class="c1" target="_blank">平方</a> <a href="/tags/908/" title="平方根" class="c1" target="_blank">平方根</a> <a href="/tags/937/" title="课堂" class="c1" target="_blank">课堂</a>

4.求下列各式的值:

 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/61/" title="平方" class="c1" target="_blank">平方</a> <a href="/tags/908/" title="平方根" class="c1" target="_blank">平方根</a> <a href="/tags/937/" title="课堂" class="c1" target="_blank">课堂</a>

5.求下列各式的值:

 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/61/" title="平方" class="c1" target="_blank">平方</a> <a href="/tags/908/" title="平方根" class="c1" target="_blank">平方根</a> <a href="/tags/937/" title="课堂" class="c1" target="_blank">课堂</a>

6.如果 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/61/" title="平方" class="c1" target="_blank">平方</a> <a href="/tags/908/" title="平方根" class="c1" target="_blank">平方根</a> <a href="/tags/937/" title="课堂" class="c1" target="_blank">课堂</a> 一定等于x吗?如果x是任意一个数, <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/61/" title="平方" class="c1" target="_blank">平方</a> <a href="/tags/908/" title="平方根" class="c1" target="_blank">平方根</a> <a href="/tags/937/" title="课堂" class="c1" target="_blank">课堂</a> 等于什么数?

7.一个圆的半径是10cm,是它面积2倍的一个正方形的边长约为多少cm(精确到0.1cm

8.在物理学中我们知道:动能的大小取决于物体的质量与它的速度.关系式是:动能 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/61/" title="平方" class="c1" target="_blank">平方</a> <a href="/tags/908/" title="平方根" class="c1" target="_blank">平方根</a> <a href="/tags/937/" title="课堂" class="c1" target="_blank">课堂</a> ,若某物体的动能是25焦(动能单位),质量m0.7千克,求它的速度为每秒多少米?(精确到0.01

9.飞出地球,遨游太空,长久以来就是人类的一种理想,可是地球的引力毕竟太大了,飞机飞得再快,也得回到地面,导弹打得再高,也得落向地面,只有当物体的速度达到一定值时,才能克服地球引力,围绕地球旋转,这个速度我们叫做第一宇宙速度,计算式子是: <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/61/" title="平方" class="c1" target="_blank">平方</a> <a href="/tags/908/" title="平方根" class="c1" target="_blank">平方根</a> <a href="/tags/937/" title="课堂" class="c1" target="_blank">课堂</a> 千米/秒,其中重力加速度 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/61/" title="平方" class="c1" target="_blank">平方</a> <a href="/tags/908/" title="平方根" class="c1" target="_blank">平方根</a> <a href="/tags/937/" title="课堂" class="c1" target="_blank">课堂</a> 千米/2,地球半径 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/61/" title="平方" class="c1" target="_blank">平方</a> <a href="/tags/908/" title="平方根" class="c1" target="_blank">平方根</a> <a href="/tags/937/" title="课堂" class="c1" target="_blank">课堂</a> 千米,试求出第一宇宙速度的值(单位:千米/秒).

参考答案

一、选择题

1.1A 2C 3B 4C 5A 6D

二、判断题

1× 2. √ 3.√ 4× 5× 6.√

三、解答题

1.第一行依次填1112151820,第二行依次填169196256289361

2.平方根依次为:±13±19± <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/61/" title="平方" class="c1" target="_blank">平方</a> <a href="/tags/908/" title="平方根" class="c1" target="_blank">平方根</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/61/" title="平方" class="c1" target="_blank">平方</a> <a href="/tags/908/" title="平方根" class="c1" target="_blank">平方根</a> <a href="/tags/937/" title="课堂" class="c1" target="_blank">课堂</a> 0±0.6±0.11± <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/61/" title="平方" class="c1" target="_blank">平方</a> <a href="/tags/908/" title="平方根" class="c1" target="_blank">平方根</a> <a href="/tags/937/" title="课堂" class="c1" target="_blank">课堂</a> ±30

± <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/61/" title="平方" class="c1" target="_blank">平方</a> <a href="/tags/908/" title="平方根" class="c1" target="_blank">平方根</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/61/" title="平方" class="c1" target="_blank">平方</a> <a href="/tags/908/" title="平方根" class="c1" target="_blank">平方根</a> <a href="/tags/937/" title="课堂" class="c1" target="_blank">课堂</a>

算术平方根依次为:1319 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/61/" title="平方" class="c1" target="_blank">平方</a> <a href="/tags/908/" title="平方根" class="c1" target="_blank">平方根</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/61/" title="平方" class="c1" target="_blank">平方</a> <a href="/tags/908/" title="平方根" class="c1" target="_blank">平方根</a> <a href="/tags/937/" title="课堂" class="c1" target="_blank">课堂</a>00.60.11 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/61/" title="平方" class="c1" target="_blank">平方</a> <a href="/tags/908/" title="平方根" class="c1" target="_blank">平方根</a> <a href="/tags/937/" title="课堂" class="c1" target="_blank">课堂</a>30 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/61/" title="平方" class="c1" target="_blank">平方</a> <a href="/tags/908/" title="平方根" class="c1" target="_blank">平方根</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/61/" title="平方" class="c1" target="_blank">平方</a> <a href="/tags/908/" title="平方根" class="c1" target="_blank">平方根</a> <a href="/tags/937/" title="课堂" class="c1" target="_blank">课堂</a>

34,-1.21 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/61/" title="平方" class="c1" target="_blank">平方</a> <a href="/tags/908/" title="平方根" class="c1" target="_blank">平方根</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/61/" title="平方" class="c1" target="_blank">平方</a> <a href="/tags/908/" title="平方根" class="c1" target="_blank">平方根</a> <a href="/tags/937/" title="课堂" class="c1" target="_blank">课堂</a>0.14

491542 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/61/" title="平方" class="c1" target="_blank">平方</a> <a href="/tags/908/" title="平方根" class="c1" target="_blank">平方根</a> <a href="/tags/937/" title="课堂" class="c1" target="_blank">课堂</a>0.3 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/61/" title="平方" class="c1" target="_blank">平方</a> <a href="/tags/908/" title="平方根" class="c1" target="_blank">平方根</a> <a href="/tags/937/" title="课堂" class="c1" target="_blank">课堂</a>1254.15

523 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/61/" title="平方" class="c1" target="_blank">平方</a> <a href="/tags/908/" title="平方根" class="c1" target="_blank">平方根</a> <a href="/tags/937/" title="课堂" class="c1" target="_blank">课堂</a>0.4 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/61/" title="平方" class="c1" target="_blank">平方</a> <a href="/tags/908/" title="平方根" class="c1" target="_blank">平方根</a> <a href="/tags/937/" title="课堂" class="c1" target="_blank">课堂</a>350.01

6x>0时, <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/61/" title="平方" class="c1" target="_blank">平方</a> <a href="/tags/908/" title="平方根" class="c1" target="_blank">平方根</a> <a href="/tags/937/" title="课堂" class="c1" target="_blank">课堂</a> ,如果x是任意一个数, <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/61/" title="平方" class="c1" target="_blank">平方</a> <a href="/tags/908/" title="平方根" class="c1" target="_blank">平方根</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/61/" title="平方" class="c1" target="_blank">平方</a> <a href="/tags/908/" title="平方根" class="c1" target="_blank">平方根</a> <a href="/tags/937/" title="课堂" class="c1" target="_blank">课堂</a> 时, <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/61/" title="平方" class="c1" target="_blank">平方</a> <a href="/tags/908/" title="平方根" class="c1" target="_blank">平方根</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/61/" title="平方" class="c1" target="_blank">平方</a> <a href="/tags/908/" title="平方根" class="c1" target="_blank">平方根</a> <a href="/tags/937/" title="课堂" class="c1" target="_blank">课堂</a> 时, <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/61/" title="平方" class="c1" target="_blank">平方</a> <a href="/tags/908/" title="平方根" class="c1" target="_blank">平方根</a> <a href="/tags/937/" title="课堂" class="c1" target="_blank">课堂</a>

7.设正方形的边长

 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/61/" title="平方" class="c1" target="_blank">平方</a> <a href="/tags/908/" title="平方根" class="c1" target="_blank">平方根</a> <a href="/tags/937/" title="课堂" class="c1" target="_blank">课堂</a> cm

8 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/61/" title="平方" class="c1" target="_blank">平方</a> <a href="/tags/908/" title="平方根" class="c1" target="_blank">平方根</a> <a href="/tags/937/" title="课堂" class="c1" target="_blank">课堂</a> (米/秒).

97.9千米/秒.