化简求值
问题描述：
化简求值
x/(x-1)-3/(x-1)(x+2)-1
x=-（2/3）
答
x/(x-1)-3/(x-1)(x+2)-1=x(x+2)/(x-1)(x+2)-3/(x-1)(x+2)-(x-1)(x+2)/(x-1)(x+2)=[x(x+2)-3-(x-1)(x+2)]/(x-1)(x+2)=[x^2+2x-3-(x-1)(x+2)]/(x-1)(x+2)=[(x+3)(x-1)-(x-1)(x+2)]/(x-1)(x+2)=(x-1)[(x+3)-(x+2)]/(x-1...