(5a-4b)(b/5+a/4)expand by using idenities.?
回答 (1)
2015-12-30 2:21 pm
(5a-4b)(b/5+a/4)
=ab+1.25a^2-0.8b^2 -ab
=(25a^2 -20b^2)/20
=ab+1.25a^2-0.8b^2 -ab
=(25a^2 -20b^2)/20
收錄日期: 2021-04-18 14:14:22
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20151228193142AAOYIfr