用两种方法计算:(x/x-2-x/x+2)÷4x/2-x

问题描述:

用两种方法计算:(x/x-2-x/x+2)÷4x/2-x
分别运用分式乘除法、加减法.

[x/(x-2)-x/(x+2)]÷4x/(2-x)
=[x/(x-2)-x/(x+2)]×(2-x)/4x
=[(x+2-x+2)/(x+2)(x-2)]*(2-x)/4
=-1/(x+2)