试题与答案

所有的质数加1后，就变成了合数．______．

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题型：解答题

题目：

所有的质数加1后，就变成了合数．______．

答案：

根据质数的意义可知：

最小的质数为2，2+1=3，3为质数；

所以，“所有的质数加1后，就变成了合数”的说法是错误的．

故答案为：错误．

考点：质数，互质数，分解质因数，合数
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