$Bài_{}$ $2:_{}$ $a)_{}$ $-3x-6xy+9xz_{}$
$=-3x.(1+2y-3z)_{}$
$b)_{}$ $9x^3y^2+3x^2y^2_{}$
$=3x^2y^2.(3x+1)_{}$
$c)_{}$ $4x^3y^2-8x^2y^3+2x^4y_{}$
$=2x^2y.(2xy-4y^2+x^2)_{}$
$d)_{}$ $7x^2y^2-21xy^2z+7xyz-14xy_{}$
$=7xy.(xy-3yz+z-2)_{}$
$Bài_{}$ $3:_{}$
$a)_{}$ $3x.(x-1)+5.(x-1)_{}$
$=(3x+5)(x-1)_{}$
$b)_{}$ $3x.(y+2)-3.(y+2)_{}$
$=(3x-3)(y+2)_{}$
$=3.(x-1)(y+2)_{}$
$c)_{}$ $5x^2.(x-2y)-15x.(x-2y)_{}$
$=(5x^2-15x)(x-2y)_{}$
$=5x.(x-3)(x-2y)_{}$
$d)_{}$ $5x.(x-2)-3x^2.(x-2)_{}$
$=(5x-3x^2)(x-2)_{}$
$=x.(5-3x)(x-2)_{}$
$Bài_{}4:$
$a)_{}$ $3x.(x-1)+5.(1-x)_{}$
$=3x.(x-1)-5.(x-1)_{}$
$=(3x-5)(x-1)_{}$
$b)_{}$ $2.(2x-1)+3.(1-2x)_{}$
$=2.(2x-1)-3.(2x-1)_{}$
$=(2x-1)(2-3)_{}$
$=-(2x-1)_{}$
$c)_{}$ $x^2.(x-1)+16.(1-x)_{}$
$=x^2.(x-1)-16.(x-1)_{}$
$=(x^2-16).(x-1)_{}$
$=(x-4)(x+4)(x-1)_{}$
$d)_{}$ $10x.(x-y)-8y.(y-x)_{}$
$=10x.(x-y)+8y.(x-y)_{}$
$=(10x+8y)(x-y)_{}$
$=2.(5x+4y)(x-y)_{}$
$Bài_{}$ $5:_{}$
$a)_{}$ $x^2-y^2-2x+2y_{}$
$=(x-y)(x+y)-2.(x-y)_{}$
$=(x-y)(x+y-2)_{}$
$b)_{}$ $2x^2+3x-2xy-3y_{}$
$=x.(2x+3)-y.(2x+3)_{}$
$=(x-y)(2x+3)_{}$
$c)_{}$ $xz+yz-5x-5y_{}$
$=z.(x+y)-5.(x+y)_{}$
$=(x+y)(z-5)_{}$
$d)_{}$ $(x+3)^2-(2x-5)(x+3)_{}$
$=(x+3).[ x+3-(2x-5)]_{}$
$=(x+3)(x+3-2x+5)_{}$
$=(x+3)(-x+8)_{}$
#Chúc bạn học tốt !
