logx-logy=log(x-y),用y表示x,
问题描述:
logx-logy=log(x-y),用y表示x,
答
易知x>y>0
log(x/y)=log(x-y)
x/y=x-y
x=yx-y²
(y-1)x=y²
x=y²/(y-1) (y>1)