Question

[Khánh Huyền]

Thực hiện phép tính

( x - 1).( x +1). ( x + 2)

Answer 1

[Nobi Nobita]

Ta có:

\(\left(x-1\right).\left(x+1\right).\left(x+2\right)\)

\(=\left(x^2+x-x-1\right).\left(x+2\right)\)

\(=\left(x^2-1\right).\left(x+2\right)\)

\(=x^3+2x^2-x-2\)