Question

x²+4xy-4z²+4y²

Answer 1

= x^2+4xy+4y^2 -4z^2

= (x+2y)^2 -4z^2

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

Answer 2

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

Answer 3

=x²+4xy+4y²-4z²

=(x+2y)²-4z²

=(x+2y-4z)(x+2y+4z)

chắc chắn đúng

Answer 4

x²+4xy-4z²+4y2
(x+2)²-2z²
(x+2-2z)(x+2+2z)
 

Answer 5