(81-x^4)/(x^2+9)/(x-3)

分类: 作业答案 • 2022-04-02 16:23:35

问题描述：

答

(81-x^4)/(x^2+9)/(x-3)
=(9-x^2)*(9+x^2)/(x^2+9)/(x-3)
=(3-x)(3+x)/(x-3)
=-(x+3)但我怎么觉得最后答案是 x+33 - x =-(x-3)