Đáp án + Giải thích các bước giải:
$#hyn$
$4x.(x-2y)+8y.(2y-x)$
$=4x.(x-2y)-8y.(x-2y)$
$=(x-2y).(4x-8y)$
$=(x-2y).4.(x-2y)$
$=4.(x-2y)^2$
$(x+1)^4+(x^2+x+1)^2$
$=(x+1)^4+(x^4+x^2+1+2x^3+2x+2x^2)$
$=(x+1)^4+(x+1)^2+x^2.(x^2+2x+2)$
$=(x+1)^2.[(x+1)^2+1]+x^2.(x^2+2x+2)$
$=(x+1)^2.[x^2+2x+1+1]+x^2.(x^2+2x+2)$
$=(x+1)^2.(x^2+2x+2)+x^2.(x^2+2x+2)$
$=(x^2+2x+1).[(x+1)^2+x^2]$
$=(x^2+2x+2).[x^2+2x+1+x^2]$
$=(x^2+2x+2).(2x^2+2x+1)$
