Question

过程，给好评

Answer 1

（1）=2(x+3)/(x^2-9)-6/(x^2-9)= 2x/(x^2-9)
(2)=1/3x+x/(3x-2)= (3x^2+3x-2)/3x(3x-2)

追问

帮帮忙

化简一下就行了

追答

2(r+1)/(r+1)^2+(r-1)/(r+1)+r = 2/（r+1)++(r-1)/(r+1)+r = 1+r = 101.

[2n*(2n-m)+m(2n+m)+4mn]÷(4n^2-m^2) = (2n+m)^2/(2n+m)(2n-m) = (2n+m)/(2n-m) = (2n+n/5)/(2n-n/5) = 11/9

追问

谢谢啊