\(x^2-x-xy-2y^2+2y\)

\(=x^2-x-2xy+xy-2y^2+2y\)

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

\(=2y\left(-y-x+1\right)-x\left(-y-x+1\right)\)

\(=\left(2y-x\right)\left(-y-x+1\right)\)

\(1,=x\left(x^2-2x+1-y^2\right)=x\left[\left(x-1\right)^2-y^2\right]=x\left(x-y-1\right)\left(x+y-1\right)\\ 2,=\left(x+y\right)^3\\ 3,=\left(2y-z\right)\left(4x+7y\right)\\ 4,=\left(x+2\right)^2\\ 5,Sửa:x\left(x-2\right)-x+2=0\\ \Leftrightarrow\left(x-2\right)\left(x-1\right)=0\Leftrightarrow\left[{}\begin{matrix}x=1\\x=2\end{matrix}\right.\)

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

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

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

(x-2)(x+y)

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

bạn rút x ra rồi tính ❕

= ( x³ + 2x²y + xy² ) - 16x

= x (x² + 2xy + y²) - 16x

= x( x + y)² - 16x

= x [ ( x + y)² - 16 ]

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

=x.(x²+2xy+y²-16)

=x.[(x+y)²-16]

=x.(x+y-4).(x+y+4)

a) xy+3x-7y-21

=x(y+3)-7(x+3)

=(x-7)(y+3)

b)2xy-15-6x-5y

=2x(y-3)-5(-3+y)

=(2x-5)(y-3)

c)2x^2y+2xy^2-2x-2y

=2x(xy-1)+2y(xy-1)

=(2x+2y)(xy-1)

x(x+3)-5x(x-5)-5(x+3)

=(x-5)(x+3)-5x(x-5)

=(x-5)(x+3-5x)

Câu cuối mình bị nhầm dòng cuối phải là (x-5)(x+3+x-5)=(x-5)(2x-2)nha bạn

a) xy+3x-7y-21=(xy+3x)-(7y+21)= x(y+3)-7(y+3)=(y+3)(x-7)

b)2xy-15-6x+5y=(2xy-6x)+(5y-15)=2x(y-3)+5(y-3)=(y-3)(2x+5)

c)2x^2y+2xy^2-2x-2y=2xy(x+y)-2(x+y)=2(x+y)(xy-1)

d) x(x+3)-5x(x-5)-5(x+3)=[x(x+3)-5(x+3)]-5x(x-5)=(x+3)(x-5)-5x(x-5)=(x-5)(x+3-5x)=(x-5)(3-4x)

1) \(x^2-y^2-2x-2y\)

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

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

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

2) \(3x^2-3y^2-2\left(x-y\right)^2\)

\(=3\left(x^2-y^2\right)-2\left(x-y\right)^2\)

\(=3\left(x-y\right)\left(x+y\right)-2\left(x-y\right)^2\)

\(=\left(x-y\right)\left[3\left(x+y\right)-2\left(x-y\right)\right]\)

\(=\left(x-y\right)\left(3x+3y-2x+2y\right)\)

\(=\left(x-y\right)\left(x+5y\right)\)

1) x² - y² - 2x - 2y

= (x² - y²) - (2x + 2y)

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

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

2) 3x² - 3y² - 2(x - y)²

= (3x² - 3y²) - 2(x - y)²

= 3(x² - y²) - 2(x - y)²

= 3(x - y)(x + y) - 2(x - y)²

= (x - y)[3(x + y) - 2(x - y)]

= (x - y)(3x + 3y - 2x + 2y)

= (x - y)(x + 5y)

`x^2-y^2 -2x-2y`

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

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

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

__

`3x^2 -3y^2 -2(x-y)^2`

`= 3(x^2 -y^2) - 2(x-y)^2`

`=3(x-y)(x+y) -2(x-y)^2`

`= (x-y) (3x+3y -2x+2y)`

`=(x-y)( x+5y)`

1.A

2.C

3.B

4.C

a

c

b

c

(x-1)y^2-4(x-1)y

^2 + 4xy - 16 + 4y^2 
= x^2 + 4xy + 4y^2 - 4^2 
= (x + 2y)^2 - 4^2 
= (x + 2y - 4)(x + 2y + 4) 
2x^2-5xy-3y^2 
= 2^x + xy - 6xy - 3y^2 
= x(2x + y) - 3y(2x + y) 
= (2x + y)(x - 3y)

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