计算:3/x+1-12/x^2-1-6/1-x

问题描述:

计算:3/x+1-12/x^2-1-6/1-x

3/x+1-12/x^2-1-6/1-x
=3/(x+1)-12/(x+1)(x-1)+6/(x-1)
=[3(x-1)-12+6(x+1)]/(x+1)(x-1)
=(9x-9)/(x+1)(x-1)
=9/(x+1)