求值：(x/x^2-1)除以(x^2+4x+3)/(x^2+2x+1)
问题描述：
求值：(x/x^2-1)除以(x^2+4x+3)/(x^2+2x+1)
答
=(x/x^2-1)*[(x^2+2x+1) /(x^2+4x+3)]
=[x/(x+1)(x-1)]*[(x+1)^2/(x+3)(x+1)]
约去相同项得
=x/[(x-1)(x+3)]