热血传奇千年寒冰:一道数学题 急用

来源:百度文库 编辑:高考问答 时间:2024/05/09 03:36:23
利用整式乘法公式进行计算:
(a^2+a-4)(a^2-a-4)

(a^2+a-4)(a^2-a-4)=[(a^2-4)+a][(a^2-4)-a]=(a^2-4)^2-a^2=a^4-9a^2+16

(a^2+a-4)(a^2-a-4)
=[(a^2-4)+a][(a^2-4)-a]
=(a^2-4)^2-a^2
=a^4-8a^2+16-a^2
=a^4-9a^2+16

原式=(a^2-4)^2-a^2
=a^4-8a^2+16-a^2=a^4-9a^2+16

(a^2+a-4)(a^2-a-4)
=(a^2-4)^2-a^2
=a^4-8a^2+16-a^2
=a^4-9a^2+16

(a^2+a-4)(a^2-a-4)
=[(a^2-4)+a][(a^2-4)-a]
=(a^2-4)^2-a^2
=a^4-8a^2+16-a^2
=a^4-9a^2+16

原式=(a^2-4)^2-a^2
=a^4-8a^2+16-a^2=a^4-9a^2+16