非负数的概念和性质在中学数学中占有一定的地位和作用,这从近几年各省市中考试题中也反映了这一点.而学生往往对非负数的概念认识不清,尤其是算术根是一个非负数,不能自觉地运用.因此,有必要结合具体例子进行系统地复习. The concept and nature of non-negative numbers play a certain role and role in middle school mathematics. This has also been reflected in the exam questions of provinces and cities in recent years. Students often have unclear understanding of the concept of non-negative numbers, especially the arithmetic roots. A non-negative number cannot be used consciously. Therefore, it is necessary to systematically review it with specific examples.