Question

x²-9+(x-3)²

Answer 1

Ta có :

\(x^2-9+\left(x-3\right)^2=\left(x-3\right)\left(x+3\right)+\left(x-3\right)^2=\left(x-3\right)\left(x+3+x-3\right)=2x\left(x-3\right)\)

Answer 2

\(x^2-9+\left(x-3\right)^2=\left(x-3\right)\left(x+3\right)+\left(x-3\right)^2=\left(x-3\right)\left(x+3+x-3\right)=2x\left(x-3\right)\)

CHÚC BẠN HỌC GIỎI