12a^4-3a[a²-4a(a³-2a+3a)]= 3(x^2-2)-5x(x+1)+4x(1-x)=?

12a^4-3a[a²-4a(a³-2a+3a)]= 3(x^2-2)-5x(x+1)+4x(1-x)=?
12a^4-3a[a²-4a(a³-2a+3a)]= 3(x^2-2)-5x(x+1)+4x(1-x)=?

12a^4-3a[a²-4a(a³-2a+3a)]= 3(x^2-2)-5x(x+1)+4x(1-x)=?
12a^4-3a[a²-4a(a²-2a+3)]=12a^4-3a(a²-4a³+8a²-12a)=12a^4-3a³-12a^4-24a³+36a²
=-27a³+36a²
你的题目有没有错
3(x^2-2)-5x(x+1)+4x(1-x)=3x²-6-5x²-5x+4x-4x²=-6x²-x-6

你要求啥？