(3m²-n²)²-(m²-3n²)²=
问题描述：
(3m²-n²)²-(m²-3n²)²=
答
(3m²-n²)²-(m²-3n²)²=(3m^2-n^2+m^2-3n^2)*(3m^2-n^2-m^2+3n^2)=(4m^2-4n^2)*(2m^2+2n^2)=8*(m^2-n^2)*(m^2+n^2) (1)=8*(m^4-n^4)=8m^4-8n^4 (2)如果因式分解,则到(1)如果化简,则到(2...