if x²+ 1/ x² = 3, then (x- 1/x) ² =?
expand by using identity: 1/3(x+3)(x-3)
需要列明部驟, thanks
2題多項式數學題, 15分
2008-11-25 10:15 am
回答 (1)
2008-11-25 10:43 am
✔ 最佳答案
(x-1/x)^2=x^2-2+1/x^2
=3-2
=1
1/3(x+3)(x-3)
=1/3(x^2-3^2)
=1/3(x^2-9)
=(1/3)x^2-3
收錄日期: 2021-04-25 16:58:36
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20081125000051KK00163