计算(x-1分之x^2)-x-1 分式加减法
问题描述：
计算(x-1分之x^2)-x-1 分式加减法
答
原式=[x²/(x-1)]-x-1
=[x²/(x-1)]-[(x+1)(x-1)]/(x-1)
=[x²/(x-1)]-(x²-1)/(x-1)
=[x²-(x²-1)]/(x-1)
=1/(x-1)