y=[(x^2-2x+1)/(x^2-1)]÷[(x^2-x)/(x+1)]*5x
=[(x-1)^2/(x-1)(x+1)]÷[x(x-1)/(x+1)]*5x
=[(x-1)/(x+1)]÷[x(x-1)/(x+1)]*5x
=(1÷x)*5x
=5
你能明白,赞同