請詳列計算過程!!!!!!!!!!!!!!!!!!!
圖片參考：http://imgcld.yimg.com/8/n/HA00763813/o/700911110149013873408310.jpg
f.4 maths 20marks!!!!!!!!!!!!!
2009-11-12 5:02 am
回答 (1)
2009-11-12 5:19 am
✔ 最佳答案
| 2x + 3 | > 4(2x + 3)^2 > 16
4x^2 + 12x + 9 - 16 > 0
4x^2 + 12x - 7 > 0
(2x + 7)(2x - 1) > 0
x < -7/2 or x > 1/2
1. C(n+1,0) + C(n,0)
= (n+1)!/[(n+1)!0!] + n!/[n!0!]
= 1 + 1
= 2
2. 1/n! - 1/(n+1)!
= (n+1)/(n+1)! - 1/(n+1)!
= n/(n+1)!
收錄日期: 2021-04-23 23:19:44
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20091111000051KK01490