当前位置:首页 > 八年级 > 数学试卷

【330731】二次根式习题

时间:2025-02-11 18:40:14 作者: 字数:1295字

二次根式习题

一、选择题

1.下列式子中,是二次根式的是( )

A- <a href="/tags/198/" title="习题" class="c1" target="_blank">习题</a> <a href="/tags/896/" title="根式" class="c1" target="_blank">根式</a> B <a href="/tags/198/" title="习题" class="c1" target="_blank">习题</a> <a href="/tags/896/" title="根式" class="c1" target="_blank">根式</a> C <a href="/tags/198/" title="习题" class="c1" target="_blank">习题</a> <a href="/tags/896/" title="根式" class="c1" target="_blank">根式</a> Dx

2.下列式子中,不是二次根式的是( )

A <a href="/tags/198/" title="习题" class="c1" target="_blank">习题</a> <a href="/tags/896/" title="根式" class="c1" target="_blank">根式</a> B <a href="/tags/198/" title="习题" class="c1" target="_blank">习题</a> <a href="/tags/896/" title="根式" class="c1" target="_blank">根式</a> C <a href="/tags/198/" title="习题" class="c1" target="_blank">习题</a> <a href="/tags/896/" title="根式" class="c1" target="_blank">根式</a> D <a href="/tags/198/" title="习题" class="c1" target="_blank">习题</a> <a href="/tags/896/" title="根式" class="c1" target="_blank">根式</a>

3.已知一个正方形的面积是5,那么它的边长是( )

A5 B <a href="/tags/198/" title="习题" class="c1" target="_blank">习题</a> <a href="/tags/896/" title="根式" class="c1" target="_blank">根式</a> C <a href="/tags/198/" title="习题" class="c1" target="_blank">习题</a> <a href="/tags/896/" title="根式" class="c1" target="_blank">根式</a> D.以上皆不对

二、填空题

1.形如________的式子叫做二次根式.

2.面积为a的正方形的边长为________

3.负数________平方根.

三、综合提高题

1.某工厂要制作一批体积为1m3的产品包装盒,其高为0.2m,按设计需要,底面应做成正方形,试问底面边长应是多少?

2.当x是多少时, <a href="/tags/198/" title="习题" class="c1" target="_blank">习题</a> <a href="/tags/896/" title="根式" class="c1" target="_blank">根式</a> +x2在实数范围内有意义?

3.若 <a href="/tags/198/" title="习题" class="c1" target="_blank">习题</a> <a href="/tags/896/" title="根式" class="c1" target="_blank">根式</a> + <a href="/tags/198/" title="习题" class="c1" target="_blank">习题</a> <a href="/tags/896/" title="根式" class="c1" target="_blank">根式</a> 有意义,则 <a href="/tags/198/" title="习题" class="c1" target="_blank">习题</a> <a href="/tags/896/" title="根式" class="c1" target="_blank">根式</a> =_______

4.使式子  <a href="/tags/198/" title="习题" class="c1" target="_blank">习题</a> <a href="/tags/896/" title="根式" class="c1" target="_blank">根式</a> 有意义的未知数x有( )个.

A0 B1 C2 D.无数

5.已知ab为实数,且 <a href="/tags/198/" title="习题" class="c1" target="_blank">习题</a> <a href="/tags/896/" title="根式" class="c1" target="_blank">根式</a> +2 <a href="/tags/198/" title="习题" class="c1" target="_blank">习题</a> <a href="/tags/896/" title="根式" class="c1" target="_blank">根式</a> =b+4,求ab的值.

答案:

一、1A 2D 3B

二、1 <a href="/tags/198/" title="习题" class="c1" target="_blank">习题</a> <a href="/tags/896/" title="根式" class="c1" target="_blank">根式</a>a≥02 <a href="/tags/198/" title="习题" class="c1" target="_blank">习题</a> <a href="/tags/896/" title="根式" class="c1" target="_blank">根式</a> 3.没有

三、1.设底面边长为x,则0.2x2=1,解答:x= <a href="/tags/198/" title="习题" class="c1" target="_blank">习题</a> <a href="/tags/896/" title="根式" class="c1" target="_blank">根式</a>

2.依题意得: <a href="/tags/198/" title="习题" class="c1" target="_blank">习题</a> <a href="/tags/896/" title="根式" class="c1" target="_blank">根式</a> <a href="/tags/198/" title="习题" class="c1" target="_blank">习题</a> <a href="/tags/896/" title="根式" class="c1" target="_blank">根式</a>

x>- <a href="/tags/198/" title="习题" class="c1" target="_blank">习题</a> <a href="/tags/896/" title="根式" class="c1" target="_blank">根式</a> x≠0时,  <a href="/tags/198/" title="习题" class="c1" target="_blank">习题</a> <a href="/tags/896/" title="根式" class="c1" target="_blank">根式</a> x2在实数范围内没有意义.

3. <a href="/tags/198/" title="习题" class="c1" target="_blank">习题</a> <a href="/tags/896/" title="根式" class="c1" target="_blank">根式</a> 4B 5a=5b=-4