Q15:
If p is the product of the integers from 1 to 30, inclusive, what is the greatest integer k for which 3^k is a factor of p?
A. 10
B. 12
C. 14
D. 16
E. 18
Ans: C
請問這題是跟因數倍數有關係嘛 ? 有公式嘛?
我想或許很簡單...但是就是想不到怎麼算...
煩請勞駕...指點迷津...感恩 ~~