6(X^2+1/(X^2))+5(X+1/X)-50=0
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訪客 (未驗證)

2006-02-11 19:49
6(X^2+1/(X^2))+5(X+1/X)-50=0
=>(同乘X^2) 6(X^2+1)+5(X^2)=50
=>X^12+6+X^10=50
=>X^22=44
=>X^=2
=>X=正負根號2

Flywithwings

2006-02-11 20:04
6 (X^2+1/(X^2))+5(X+1/X)-50=0
=> (同乘X^2) 6(X^2+1)+5(X^2)=50
=>X^12+6+X^10=50
=>X^22=44
=>X^=2
=>X=正負根號2 (忘了登入><)

訪客 (未驗證)

2006-02-11 21:11
6 (X^2+1/(X^2))+5(X+1/X)-50=0
=> (同乘X^2) 6(X^2+1)+5(X^2)=50

你好像有計算錯誤

willy

2006-02-11 21:13
6 (X^2+1/(X^2))+5(X+1/X)-50=0
=> (同乘X^2) 6(X^2+1)+5(X^2)=50

你好像有計算錯誤

Flywithwings

2006-02-11 21:48
sorry剛剛有點算錯

6(X^2+1/(X^2))+5(X+1/X)-50=0
=>(同乘X^2) 6(X^2+1)+5X(X+1)-50X^2=0
=>39X^2 -5X-6=0
=>(十字交乘) (13X-6)(3X+1)=0
=>13X=6 or 3X=-1
=>X= 6/13 or - 1/3

若是還有錯誤請各位朋友們不吝指教！謝謝 ^_^

蔡宗翰

2006-02-11 21:59
同㘾X^2會變成
6(X^4+1)+5X(X^2+1)-50X^2=0
....

ac19920221

2006-02-11 22:00
答案帶入不合

linian

2006-02-11 23:46
可以分解嗎??

mathematical2005

2006-02-12 12:35
你們是不是看錯題目了
6((X^2)+(1/(X^2)))+5(X+(1/X))-50=0

mathematical2005

2006-02-12 12:35
這樣有清楚點兒嗎

aa963854116

2006-02-12 13:17
令x+1/x=a
則x^2+1/x^2=a^2-2
原方程變為
6a^2+5a-62=0
求出a再求x
可是不好解ㄝ
不是有理數