Question

\(9a^2 -18ab +9b^2 -36c^2\)

phân tích thành nhân tử

Answer 1

\(=9\left(a^2-2ab+b^2-4c^2\right)\)

\(=9\left[\left(a-b\right)^2-\left(2c\right)^2\right]\)

=9(a-b-2c)(a-b+2c)

Answer 2

`9a^2-18ab+9b^2-36c^2`

`=9(a^2-2ab+b^2-4c^2)`

`=9[(a-b)^2-(2c)^2]`

`=9(a-b-2c)(a-b+2c)`