利用平方差的恆等式,把下列分解為因式
(請清楚列明橫式)
(1-x)(1-x)-81
中二數,用恆等式化為因式
2007-11-16 9:32 pm
回答 (2)
2007-11-17 12:02 am
(1-x)(1-x)-81
= (1-x)^2 - 9^2
= (1-x-9)(1-x+9)
= (-8-x)(10-x)
=-(8+x)(10-x)
=(x+8)(x-10)
= (1-x)^2 - 9^2
= (1-x-9)(1-x+9)
= (-8-x)(10-x)
=-(8+x)(10-x)
=(x+8)(x-10)
2007-11-16 11:22 pm
(1-X)(1-X) - 81
=> (1-X)^2 - (9)^2
=> [(1-X)+9] [(1-X) - 9]
=> (10-X) (8 - X)
=> X = 8 or 10
=> (1-X)^2 - (9)^2
=> [(1-X)+9] [(1-X) - 9]
=> (10-X) (8 - X)
=> X = 8 or 10
收錄日期: 2021-04-19 01:08:57
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20071116000051KK01287