a) 8 - 27x³

= (2 - 3x) (4 + 6x + 9x²)

b) 5x²y - 10xy - 5y²

= 5y(x² - 2x - y)

c) x³ + 8y³

= (x + 2y) (x² - 2xy + 4y²)

d) 3x² + 5y - 3xy - 5x

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

a, 2xy^2 ( x^3 -3xy - 4 )

b, x^2 - 4x - 4x +16

= x(x-4) - 4(x-4)

= (x-4) (x-4)

Lời giải:

a.

$2x^4y^2-6x^2y^3-8xy^2=2xy^2(x^3-3xy-4)$

b. 

$x^2-8x+16=x^2-2.4.x+4^2=(x-4)^2$

c.

$12x^2-12=12(x^2-1)=12(x-1)(x+1)$

d. 

$5x^2y-20xy+20y=5y(x^2-4x+4)=5y(x-2)^2$
e.

$3x^2y^2-27y^2=3y^2(x^2-9)=3y^2(x-3)(x+3)$

f. 

$8x^3-27y^3=(2x)^3-(3y)^3=(2x-3y)(4x^2+6xy+9y^2)$

g.

$4x^4-8x^3+4x^2=(2x^2)^2-2.2x^2.2x+(2x)^2$

$=(2x^2-2x)^2=[2x(x-1)]^2=4x^2(x-1)^2$
h.

$7x^2y^2-28y^4=7y^2(x^2-4y^2)=7y^2(x-2y)(x+2y)$

$

\(5x^2y-xy=xy\left(5x-1\right)\)

\(5 x 2 y − x y = x y ( 5 x − 1 )\)

5x2y - xy = xy (5x - 1)

\(=5x\left(x^2-2xy+y^2\right)\)

\(=5x\left(x-y\right)^2\)

Phân tích thành nhân tử:

\(5x^3-10x^2y+5xy^2=5x\left(x^2-2xy+y^2\right)=5x\left(x-y\right)^2\)

Chúc bạn học tốt!!!

\(5x^3-10x^2y+5xy^2\)

\(=5x\left(x^2-2xy+y^2\right)\)

\(=5x\left(x-y\right)^2\)

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

b: \(=5x\left(y^2-2yz+z^2\right)=5x\left(y-z\right)^2\)

=3(x²-4y²)

5x(y²-2yz + z²)

=5x(y+z)²

(5x2y – 5xy2 + xy) + (xy – x2y2 + 5xy2)

= 5x2y – 5xy2 + xy + xy – x2y2 + 5xy2

= 5x2y + (5xy2 – 5xy2) + (xy + xy) – x2y2

= 5x2y + 2xy – x2y2

a) \(=x^3\left(x-1\right)-\left(x-1\right)=\left(x-1\right)\left(x^3-1\right)\)

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

b) \(=xy\left(x+y\right)-\left(x+y\right)=\left(x+y\right)\left(xy-1\right)\)

c) Đổi đề: \(a^2x+a^2y-7x-7y\)

\(=a^2\left(x+y\right)-7\left(x+y\right)=\left(x+y\right)\left(a^2-7\right)\)

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

e) \(=x^3\left(x+1\right)+\left(x+1\right)=\left(x+1\right)\left(x^3+1\right)\)

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

g) \(=\left(x-y\right)^2-z\left(x-y\right)=\left(x-y\right)\left(x-y-z\right)\)

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

i) \(=\left(x+1\right)^2-4=\left(x+1-2\right)\left(x+1+2\right)=\left(x-1\right)\left(x+3\right)\)

a\(x^3\left(x-1\right)-\left(x-1\right)=\left(x-1\right)\left(x^3-1\right)\)

b)\(=xy\left(x+y\right)-\left(x+y\right)=\left(x+y\right)\left(xy-1\right)\)

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

e)\(=x^3\left(x+1\right)+\left(x+1\right)=\left(x+1\right)\left(x^3+1\right)\)

g)\(=\left(x-y\right)^2-z\left(x-y\right)=\left(x-y\right)\left(x-y-z\right)\)

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

i)\(=\left(x-1\right)^2-4=\left(x-1-2\right)\left(x-1+2\right)=\left(x-3\right)\left(x+1\right)\)

Hửm đề sai rồi phải là:

`a^2+2b^2-3ab`

`=a^2-ab-2ab+2b^2`

`=a(a-b)-2b(a-b)`

`=(a-b)(a-2b)`