-3(3a^2-4)-(a^2-3a+5)+(4a-a^2),a=-3

问题描述:

-3(3a^2-4)-(a^2-3a+5)+(4a-a^2),a=-3
化简求值

解-3(3a^2-4)-(a^2-3a+5)+(4a-a^2)
=-9a²+12-a²+3a-5+4a-a²
=-11a²+7a+7
=-11×(-3)²+7(-3)+7
=-99-21+7
=-113