Question

(a+1)²（a-1)²等于多少求过程

Answer 1

(a+1)²（a-1)²=（a²-1)²=a四次方-2a²+1

Answer 2

原式=[（a+1)(a-1)]²
= (a²-1)²
=a^4 -2a²+1

Answer 3

(a+1)²（a-1)²=[(a+1)(a-1)]²=(a²-1)²=a^4-2a²+1

追问

答案等于多少是不是-1

追答

答案等于多少是不是-1
??????

Answer 4

=（a^2-1)²
=a^4-2a^2+1