[1-(2)/(x+1）²÷ (x-1)/(x+1)晕 ......貌似写错了 是 【1-(2)/(x+1）】²÷ (x-1)/(x+1)

[1-(2)/(x+1）²÷ (x-1)/(x+1)晕 ......貌似写错了 是 【1-(2)/(x+1）】²÷ (x-1)/(x+1)
[1-(2)/(x+1）²÷ (x-1)/(x+1)
晕 ......
貌似写错了 是 【1-(2)/(x+1）】²÷ (x-1)/(x+1)

[1-(2)/(x+1）²÷ (x-1)/(x+1)晕 ......貌似写错了 是 【1-(2)/(x+1）】²÷ (x-1)/(x+1)
把1通分,成（x+1）/（x+1）,然后中括号内就成了（x-1）/（x+1）,然后÷ (x-1)/(x+1)成×（x+1）/（x-1）,也就是结果就是（x-1）/（x+1）