IS THIS TURE? (PROVE IF IT IS TURE OR NOT)
a/b+b/a MUST ≧ 2
IS THIS TURE? (PROVE IF IT IS TURE OR NOT)
1 maths Q (IS THIS TURE?)
2011-11-16 6:34 pm
回答 (1)
2011-11-16 7:32 pm
✔ 最佳答案
(a/b)+(b/a)= (a^2 + b^2) / ab
= [(a-b)^2 + 2ab] / ab
= [(a-b)^2]/ab + 2
as (a-b)^2 always > 0 and a, b > 0, the first term [(a-b)^2]/ab ≧ 0
implies (a/b)+(b/a) is always ≧ 2
收錄日期: 2021-04-13 18:21:38
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20111116000051KK00170