x-1分子x-(x-1)(x+2)分子3-2

来源:学生作业帮助网 编辑:作业帮 时间:2024/05/09 13:21:24
x-1分子x-(x-1)(x+2)分子3-2

x-1分子x-(x-1)(x+2)分子3-2
x-1分子x-(x-1)(x+2)分子3-2

x-1分子x-(x-1)(x+2)分子3-2
原式=[x/(x-1)]-3/[(x-1)(x+2)]-2
={ x(x+2)/[(x-1)(x+2)] }-3/[(x-1)(x+2)]-{ 2(x-1)(x+2)/[(x-1)(x+2)] }
=[x(x+2)-3-2(x-1)(x+2)]/[(x-1)(x+2)]
=(x²+2x-3-2x²-2x+4)/[(x-1)(x+2)]
=(-x²+1)/[(x-1)(x+2)]
=-(x+1)(x-1)/[(x-1)(x+2)]
= -(x+1)/(x+2)

这个是什么问题?