1/(a的平方-4a+4)-a/(a的平方-4)+1/(2a+4)

来源：学生作业学帮网编辑：学帮网时间：2024/05/14 03:58:51

1/(a的平方-4a+4)-a/(a的平方-4)+1/(2a+4)
=1/(a-2)^2-a/(a+2)(a-2)+1/2(a+2)
=[2(a+2)-2a(a-2)+(a-2)^2]/a(a+2)(a-2)^2
=-(a-4)(a+2)/2(a+2)(a-2)^2
=-(a-4)/2(a-2)^2