a*a^5+(2a^3)^2+(-2a^2)^3
问题描述：
a*a^5+(2a^3)^2+(-2a^2)^3
还有（-3a^3)^2*a^3+(-4a)^2*a^7-(5a^3)^3这一道,
答
a*a^5+(2a^3)^2+(-2a^2)^3
=a^6+4a^6-8a^6
=-3a^6
（-3a^3)^2*a^3+(-4a)^2*a^7-(5a^3)^3
=9a^6a^3+16a^2a^7-125a^9
=9a^9+16a^9-125a^9
=25a^9-125a^9
=-100a^9