发布网友 发布时间:2024-10-24 09:37
共4个回答
热心网友 时间:2024-11-09 13:05
要求的分式=(x-y)²/x²-y²
=(x-y)(x-y)/(x+y)(x-y)
=x-y/x+y
根据x:y=3 可知x=3y
所以原式=x-y/x+y=3y-y/3y+y=2y/4y=1/2
热心网友 时间:2024-11-09 13:06
1/2
热心网友 时间:2024-11-09 13:10
不会在电脑上写字 写的很难看 请见谅
热心网友 时间:2024-11-09 13:06
解:(x-y)^2/(x^2-y^2)=(x-y)(x-y)/(x+y)(x-y)=(x-y)/(x+y)
又因为x:y=3,所以x=3y,,代入得,(x-y)/(x+y)=1/2