[計量] 兩題計量請教
看板GRE (GRE入學考試)作者LouisGarneau (Louis Garneau)時間8年前 (2016/08/05 20:25)推噓4(4推 0噓 7→)留言11則, 3人參與討論串6/9 (看更多)
1.If n is a positive integer and the product of all the integers from 1 to n,
inclusive, is a multiple of 990, what is the possible value of n ?
A.8
B.10
C.12
D.14
E.16
2.If a < b < 0, which of the following numbers must be positive?
Indicate all such numbers.
A.a-b
B.a^2-b^2
C.ab
D.a^2xb
E.a^2+ab^2
第一題不懂題目的意思，選了990的因數10
答案是CDE
第二題答案是BC
想問E選項除了直接代數字（有些代入是正有些是負，剛好代到都是正）
之外有沒有其他方法？
謝謝大家。
--
※ 發信站: 批踢踢實業坊(ptt.cc), 來自: 140.112.73.1
※ 文章網址: https://www.ptt.cc/bbs/GRE/M.1470399958.A.34E.html
推
08/05 20:31, , 1F
08/05 20:31, 1F
推
08/05 20:34, , 2F
08/05 20:34, 2F
→
08/05 20:34, , 3F
08/05 20:34, 3F
→
08/05 20:48, , 4F
08/05 20:48, 4F
→
08/05 20:49, , 5F
08/05 20:49, 5F
→
08/05 20:50, , 6F
08/05 20:50, 6F
→
08/05 20:51, , 7F
08/05 20:51, 7F
推
08/05 21:21, , 8F
08/05 21:21, 8F
→
08/05 21:21, , 9F
08/05 21:21, 9F
推
08/05 21:31, , 10F
08/05 21:31, 10F
→
08/05 21:36, , 11F
08/05 21:36, 11F
討論串 (同標題文章)
GRE 近期熱門文章
PTT職涯區 即時熱門文章
10
15
