(-3a^3)·a^3+(-4a)^2a^7-(-5a^3)^3
=-3a^3·a^3+16a^2a^7-(-125a^9)
=-3a^6+16a^9+125a^9
=-3a^6+141a^9题错了。不好意思。(-3a^2)^3·a^3+(-4a)^2 a^7-(-5a^3)^3(-3a^2)^3·a^3+(-4a)^2a^7-(-5a^3)^3 =(-27a^6)·a^3+16a^2a^7-(-125a^9) =-27a^9+16a^9+125a^9 =114a^9又打错 了，。。。。。。。对不起。。。。(-3a^2)^3·a^3+(-4a)^2 a^7-(5a^3)^3(-3a^2)^3·a^3+(-4a)^2a^7-(5a^3)^3 =(-27a^6)·a^3+16a^2a^7-125a^9 =-27a^9+16a^9-125a^9 =-136a^9谢谢谢谢。不谢