Question

-2*(X-2)*(2+X)+(X-3)² rút gọn

Answer 1

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

\(=-2\left(x^2-4\right)+\left(x^2-6x+9\right)\)

\(=8-2x^2+x^2-6x+9\)

\(=-x^2-6x+17\)