Question

Answer 1

`<=> 4x^2 - x^2 + 4x - 4 = 0`

`<=> 3x^2+ 4x - 4 = 0`

`<=> 3x(x+2) - 2(x+2) = 0`

`<=> (3x-2)(x+2) = 0`

`<=> x = 2/3` hoặc `x = -2`

Answer 2

\(4x^2-\left(x-2\right)^2=0\\ \Leftrightarrow\left(4x-x+2\right)\left(4x+x-2\right)=0\\ \Leftrightarrow\left[{}\begin{matrix}3x+2=0\\5x-2=0\end{matrix}\right.\\ \Leftrightarrow\left[{}\begin{matrix}x=-\dfrac{2}{3}\\x=\dfrac{2}{5}\end{matrix}\right.\)

Answer 3

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