(4u^3+5u-7)+(8u^2-5u^3-5u-5)化简
问题描述：
(4u^3+5u-7)+(8u^2-5u^3-5u-5)化简
答
(4u^3+5u-7)+(8u^2-5u^3-5u-5)
=4u^3+5u-7+8u^2-5u^3-5u-5
=-u^3+8u^2-5