化简,求值（1+1/x-1)除以x/x平方减1,其中X=-2
问题描述：
化简,求值（1+1/x-1)除以x/x平方减1,其中X=-2
答
原式=[(x-1+1)/(x-1)]*[(x^2-1)/x]
=[x/(x-1)]*[(x+1)(x-1)/x]
=x+1
=-2+1
=-1