x的平方-1分之x-3-1+x分之2=?
问题描述：
x的平方-1分之x-3-1+x分之2=?
答
=(x-3)/(x+1)(x-1) -2(x-1)/(x+1)(x-1)
=(x-3-2x+2)/(x+1)(x-1)
=(-x-1)/(x+1)(x-1)
=-(x+1)/(x+1)(x-1)
=1/(1-x)