If n and k are positive integers, is n divisible by 6?
(1) n = k(k + 1)(k - 1)
(2) k – 1 is a multiple of 3.
答案:A
可是若K=1,那么N=0,那N就不能被6整除
若K>1,那么N能被6整除
所以(1)不能确定的啊.....
谢谢指教,我错哪儿了?
n是正整数,0不是
汗....多谢斑斑~
挨....又漏看条件了...
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