(x+1)(x-1)(x^2-1)
點樣可以
=x^4-2x^2+1
計唔到牙!!!!
F.2 maths一題
2007-11-01 3:03 am
回答 (3)
2007-11-01 3:19 am
✔ 最佳答案
先計左(x+1)(x-1)=x^2-x+x-1
=x^2-1
之後(x^2-1)(x^2-1)
x^2乘x^2 =x^4
x^2乘-1 = -x^2
-1乘x^2 = -x^2
-1乘-1 = +1
(x^2-1)(x^2-1)就=(x^4)+(-x^2)+(-x^2)+1
=x^4-2x^2+1 (中間係-數+ -數,負正得負,所以係-2x^2)
至於我唔明點解會計到x^4-4x^2+1,你不如你d步驟打出黎比人睇下你錯係邊啦
2007-11-01 7:09 am
RUBBISH
(x+1)(x-1)(x^2-1)
=(x^2-1)(x^2-1)
=(x^2-1)^2
=x^4-2x^2+1
(x+1)(x-1)(x^2-1)
=(x^2-1)(x^2-1)
=(x^2-1)^2
=x^4-2x^2+1
2007-11-01 3:14 am
(x+1)(x-1)=x^2-1
(x^2-1)(x^2-1)=x^4-2x^2+1 其中分別分三項 第一是 X^2 第二是 -1個X^2 再-1個X^2 =-2個X^2 第三: (-)(-)得正=+1
(x^2-1)(x^2-1)=x^4-2x^2+1 其中分別分三項 第一是 X^2 第二是 -1個X^2 再-1個X^2 =-2個X^2 第三: (-)(-)得正=+1
參考: MYSELF
收錄日期: 2021-04-13 14:16:38
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20071031000051KK02955