sufficient和necessary的问题FornbelongstoN,whichofthefollowing:(i)3/n(ii)9/n(iii)3/n^2(iv)12/n(v)neven^3/n(a)Is(are)necessaryforntobedivisiblebyBrieflyexplainyouranswers.(b)Is(are)suffi\x0ecientfor6jBrieflye

Question

sufficient 和necessary的问题
For n belongs to N ,which of the following :
(i) 3/n
(ii) 9/n
(iii) 3/n^2
(iv) 12/n
(v) n even ^ 3/n
(a) Is (are) necessary for n to be divisible by Briefly explain your answers.
(b) Is (are) suffi\x0ecient for 6 j Briefly explain your answers.

Answer 1

不懂你的记号.
1）3/n 指的是 n 分之 3,或是 3 整除 后者应该是 3|n.
2） 6 j n 是啥意思?