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> 如果为实数,那么一定为【】A.B.C.0D.以上均不对-八年级数学
如果为实数,那么一定为【】A.B.C.0D.以上均不对-八年级数学
题目简介
如果为实数,那么一定为【】A.B.C.0D.以上均不对-八年级数学
题目详情
如果
为实数,那么
一定为 【 】
A.
B.
C.0
D.以上均不对
题型:单选题
难度:偏易
来源:不详
答案
D
分析:算术平方根的定义:一个非负数的正的平方根,即为这个数的算术平方根,由此即可求出结果.
解答:解:
=|a|,
当a<0时,
=|a|=-a;
当a=0时,
=|a|=0;
当a>0时,
=|a|=a.
故选D.
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题目简介
如果为实数,那么一定为【】A.B.C.0D.以上均不对-八年级数学
题目详情
答案
解答:解:
当a<0时,
当a=0时,
当a>0时,
故选D.