有冇人識計-.-?
唔好直接比答案-.-
步驟詳細D
更新1:
博士呀博士@.@ 我既知識入面仲有2條數學題@.@ 幫我解答埋得唔得唷@0@
數學上的問題=.=因式分解@.@
回答 (2)
2010-04-17 2:32 am
✔ 最佳答案
60(x+2y)^2 - 38(x+2y)(x-y) - 10(x-y)^2設 a = x+2y , b = x-y ,
60a^2 - 38ab - 10b^2
= 2(30a^2 - 19ab - 5b^2)
= 2(6a - 5b)(5a + b)
= 2(6(x+2y) - 5(x-y))(5(x+2y) + x-y)
= 2 (x + 17y) (6x + 9y)
= 6(x + 17y)(2x + 3y)
2010-04-17 3:44 am
60(x+2y)^2 - 38(x+2y)(x-y) - 10(x-y)^2
2(30(x+2y)^2-19(x+2y)(x-y)-5(x-y)^2)
2((6(x+2y)-5y)(5(x+2y)+y)
2(6x+12y-5y)(5x+10y+y)
2(6x+7y)(5x+11y)
2010-04-16 19:46:50 補充：
60(x+2y)^2 - 38(x+2y)(x-y) - 10(x-y)^2
2(30(x+2y)^2-19(x+2y)(x-y)-5(x-y)^2)
2((6(x+2y)-5(x-y))(5(x+2y)+(x-y))
2(6x+12y-5x+5y)(5x+10y+x-y)
2(x+17y)(6x+9y)
6(x+17y)(2x+3y)
2010-04-16 19:47:09 補充：
The first answer is wrong
2(30(x+2y)^2-19(x+2y)(x-y)-5(x-y)^2)
2((6(x+2y)-5y)(5(x+2y)+y)
2(6x+12y-5y)(5x+10y+y)
2(6x+7y)(5x+11y)
2010-04-16 19:46:50 補充：
60(x+2y)^2 - 38(x+2y)(x-y) - 10(x-y)^2
2(30(x+2y)^2-19(x+2y)(x-y)-5(x-y)^2)
2((6(x+2y)-5(x-y))(5(x+2y)+(x-y))
2(6x+12y-5x+5y)(5x+10y+x-y)
2(x+17y)(6x+9y)
6(x+17y)(2x+3y)
2010-04-16 19:47:09 補充：
The first answer is wrong
收錄日期: 2021-04-21 22:10:09
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20100416000051KK01017