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【329573】2.6 实数 课堂练习2

时间:2025-02-02 18:24:34 作者: 字数:1415字


 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> <a href="/tags/937/" title="课堂" class="c1" target="_blank">课堂</a>

2.6 实数

一、选择题

1.下列说法中正确的是( )

A.和数轴上一一对应的数是有理数

B.数轴上的点可以表示所有的实数

C.带根号的数都是无理数

D.不带根号的数都是无理数

2.在实数中,有( )

A.最大的数 B.最小的数

C.绝对值最大的数 D.绝对值最小的数

3.实数a在数轴上的位置如图所示,则a,a, <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> <a href="/tags/937/" title="课堂" class="c1" target="_blank">课堂</a> ,a2的大小关系是( )

 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> <a href="/tags/937/" title="课堂" class="c1" target="_blank">课堂</a>

A.a<a< <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> <a href="/tags/937/" title="课堂" class="c1" target="_blank">课堂</a> <a2 B.a< <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> <a href="/tags/937/" title="课堂" class="c1" target="_blank">课堂</a> <a<a2 C.  <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> <a href="/tags/937/" title="课堂" class="c1" target="_blank">课堂</a> <a<a2<a D.  <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> <a href="/tags/937/" title="课堂" class="c1" target="_blank">课堂</a> <a2<a<a

二、填空题

4.在实数3.14, <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</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/842/" title="实数" class="c1" target="_blank">实数</a> <a href="/tags/937/" title="课堂" class="c1" target="_blank">课堂</a> ,0.13241324…, <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> <a href="/tags/937/" title="课堂" class="c1" target="_blank">课堂</a> ,π, <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> <a href="/tags/937/" title="课堂" class="c1" target="_blank">课堂</a> 中,无理数的个数是______.

5. <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> <a href="/tags/937/" title="课堂" class="c1" target="_blank">课堂</a> 的相反数是______,绝对值等于______.

6.等腰三角形的两条边长分别为 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</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/842/" title="实数" class="c1" target="_blank">实数</a> <a href="/tags/937/" title="课堂" class="c1" target="_blank">课堂</a> ,那么这个三角形的周长等于______.

7. <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> <a href="/tags/937/" title="课堂" class="c1" target="_blank">课堂</a> 是一个实数,则a=______.

8.已知m3的算术平方根,则 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> <a href="/tags/937/" title="课堂" class="c1" target="_blank">课堂</a>m< <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> <a href="/tags/937/" title="课堂" class="c1" target="_blank">课堂</a> 的解集为______.

三、解答题

9.利用勾股定理在如图所示的数轴上找出点- <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</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/842/" title="实数" class="c1" target="_blank">实数</a> <a href="/tags/937/" title="课堂" class="c1" target="_blank">课堂</a> +1.

 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> <a href="/tags/937/" title="课堂" class="c1" target="_blank">课堂</a>

10.想一想:将等式 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> <a href="/tags/937/" title="课堂" class="c1" target="_blank">课堂</a> =3 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> <a href="/tags/937/" title="课堂" class="c1" target="_blank">课堂</a> =7反过来的等式3= <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> <a href="/tags/937/" title="课堂" class="c1" target="_blank">课堂</a> 7= <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> <a href="/tags/937/" title="课堂" class="c1" target="_blank">课堂</a> 还成立吗?

式子:9 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</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/842/" title="实数" class="c1" target="_blank">实数</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/842/" title="实数" class="c1" target="_blank">实数</a> <a href="/tags/937/" title="课堂" class="c1" target="_blank">课堂</a>

4 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</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/842/" title="实数" class="c1" target="_blank">实数</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/842/" title="实数" class="c1" target="_blank">实数</a> <a href="/tags/937/" title="课堂" class="c1" target="_blank">课堂</a> 成立吗?

仿照上面的方法,化简下列各式:

12 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> <a href="/tags/937/" title="课堂" class="c1" target="_blank">课堂</a> 211 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> <a href="/tags/937/" title="课堂" class="c1" target="_blank">课堂</a> 36 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> <a href="/tags/937/" title="课堂" class="c1" target="_blank">课堂</a>






















参考答案

一、1.B 2.D 3. C

二、4.3 5. <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</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/842/" title="实数" class="c1" target="_blank">实数</a> <a href="/tags/937/" title="课堂" class="c1" target="_blank">课堂</a> 6. <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</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/842/" title="实数" class="c1" target="_blank">实数</a> <a href="/tags/937/" title="课堂" class="c1" target="_blank">课堂</a> 7.1 8.x<2

三、9.

10..成立 成立 (1 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> <a href="/tags/937/" title="课堂" class="c1" target="_blank">课堂</a> (2) <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> <a href="/tags/937/" title="课堂" class="c1" target="_blank">课堂</a> (3) <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/842/" title="实数" class="c1" target="_blank">实数</a> <a href="/tags/937/" title="课堂" class="c1" target="_blank">课堂</a>