Question

Phân tích:

x²-2x-4y²-4y

Answer 1

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

Answer 2

Ta có: \(x^2-2x-4y^2-4y\) \(=\left(x^2-4y^2\right)-\left(2x+4y\right)\)

\(=\left[x^2-\left(2y\right)^2\right]-\left(2x+4y\right)\)

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

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

Vậy \(x^2-2x-4y^2-4y=\left(x+2y\right)\left(x-2y-2\right)\)

Answer 3

x² - 2x - 4y² - 4y

= x² - ( 2y)² - 2( x + 2y)

= ( x - 2y)( x + 2y) - 2( x + 2y)

= ( x + 2y)( x - 2y - 2)