Toán Phân tích đa thức thành nhân tử : x^2 – 2x – 4y^2 – 4y Help me pls!!! 28/09/2021 By aihong Phân tích đa thức thành nhân tử : x^2 – 2x – 4y^2 – 4y Help me pls!!!
$x^{2}$ – $2x^{}$ – $4y^{2}$ – $4y^{}$ = $x^{2}$ – $2x^{}$ + $1^{}$- $4y^{2}$ – $4y^{}$ – $1^{}$ = ( $x^{2}$ – $2x^{}$ + $1^{}$ ) – ( $4y^{2}$+ $4y^{}$ + $1^{}$ ) = $(x-1)^{2}$ – $(2y+1)^{2}$ = $(x – 1 – 2y – 1 )^{}$$(x – 1 + 2y + 1 )^{}$ = $(x – 2y – 2)^{}$$(x + 2y )^{}$. Trả lời
$x^2-2x-4y^2-4y$ $=x^2-2x+1-1-4y^2-4y$ $=(x^2-2x+1)-(1+4y^2+4y)$ $=(x-1)^2-(2y+1)^2$ $=(x-1-2y-1)(x-1+2y+1)$ $=(x-2y-2)(x+2y)$ Trả lời
$x^{2}$ – $2x^{}$ – $4y^{2}$ – $4y^{}$
= $x^{2}$ – $2x^{}$ + $1^{}$- $4y^{2}$ – $4y^{}$ – $1^{}$
= ( $x^{2}$ – $2x^{}$ + $1^{}$ ) – ( $4y^{2}$+ $4y^{}$ + $1^{}$ )
= $(x-1)^{2}$ – $(2y+1)^{2}$
= $(x – 1 – 2y – 1 )^{}$$(x – 1 + 2y + 1 )^{}$
= $(x – 2y – 2)^{}$$(x + 2y )^{}$.
$x^2-2x-4y^2-4y$
$=x^2-2x+1-1-4y^2-4y$
$=(x^2-2x+1)-(1+4y^2+4y)$
$=(x-1)^2-(2y+1)^2$
$=(x-1-2y-1)(x-1+2y+1)$
$=(x-2y-2)(x+2y)$