因式分解a4-4a2-4a-1
问题描述：
因式分解a4-4a2-4a-1
答
a4-4a2-4a-1
=a^4-(2a+1)^2
=(a^2+2a+1)(a^2-2a-1)
=(a+1)^2*(a-1+√2)(a-1-√2)