F3 Maths

2011-01-12 2:26 am
如果 y^1+y^-1=2+√3 甘y^2+y^-2=?


√係開方

回答 (3)

2011-01-12 2:28 am
✔ 最佳答案
y^1 + y^-1 = 2+√3
(y^1 + y^-1)^2 = (2+√3)^2
y^2 + 2(y^1)(y^-1) + y^-2 = 4 + 4√3 + 3
y^2 + 2 + y^-2 = 7 + 4√3
y^2 + y^-2 = 5 + 4√3
參考: Knowledge is power.
2011-01-15 7:34 pm
y^1+y^-1=y+y/1=y2=2+√3=2+1.7320518=3.7320518
3.7320518/2=y=1.8660259
1.8660259^2+1.8660259^-2=3.48205265947081+0.9330195
沒時間了,下次繼續說。

2011-01-15 18:40:36 補充:
=4.41507215947081
y^2+y^-2=41507215947081

2011-01-15 18:44:06 補充:
sorry,打錯字。41507215947081是4.41507215947081。
2011-01-12 2:55 am
如果 y^1+y^-1=2+√3 甘y^2+y^-2=?
__________________________
y^1+y^-1=2+√3
(y+y^-1)^2=(2+√3)^2
y^2+2+y^-2=4+4√3+3
y^2+y^-2=5+4√3


收錄日期: 2021-04-25 17:04:37
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20110111000051KK01020

檢視 Wayback Machine 備份