Question

已知y=x加1分之x-1，试用含y的代数式表示x为

Answer 1

y(x+1)=x-1
yx+y=x-1
x-xy=y+1
x=(y+1)/(1-y)

Answer 2

y=(x-1)/(x+1)
xy+y=x-1
(y-1)x=-1-y
x=(1+y)/(1-y)