推 cs1384:(1) 2n=2*3*5*7 or 2^2*3*5*7 舉例 → 掰 08/26 13:58
→ cs1384:(2) 設 n= a*b*c*d 則 n^2=a^2*b^2*c^2*d^2 質數不變 08/26 14:00
How many different prime numbers are factors of the positive integer n ?
(1) Four different prime numbers are factors of 2n.
(2) Four different prime numbers are factors of n^2.
Answer: B
我看了PP筆記裡面的解釋
但是我還是不太懂為什麼答案是B
是否可以請各位大大解釋這一題的思路
謝謝!
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※ 編輯: denizee3 來自: 68.122.81.73 (08/26 11:57)