a) \(3x-3y=3\left(x-y\right)\)

b)\(2x^2+5x^3+x^2y=x^2\left(2+5x+y\right)\)

c)\(14x^2-21xy^2+28x^2y^2=7x\left(2x+3y^2+4xy^2\right)\)

Chúc bạn học tốt

a,\(14x^2y-21xy=7xy.\left(2x-3\right)\)

b,\(-x^2+6x-9=-\left(x^2-6x+9\right)=-\left(x-3\right)^2\)

c,\(3x^2-6xy+3y^2-27=3.\left(x^2-2xy+y^2-9\right)=3.\text{[}\left(x-y\right)^2-3^2\text{]}=3.\left(x-y-3\right).\left(x-y+3\right)\)

a) 14x²y - 21xy

= 7xy (2x - 3)

b) -x² + 6x - 9

= -(x² - 6x + 3²)

= -(x - 3)²

c) 3x² - 6xy + 3y² - 27

= 3 (x² - 2xy + y² - 9)

= 3 [(x² - 2xy + y²) - 9]

= 3 [(x - y)² - 3²]

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

#Học tốt!!!

~NTTH~

a) 3x - 3y

= 3 ( x- y )

b) 2x^2 + 5x^3 + x^2y

= x^2 ( 2+ 5x + y)

c) 14x^2 --21xy^2 + 28x^2y^2

=  7x ( 2x - 3y^2 + 4xy^2)

d) 4x^3 - 14x^2

​= x^2 ( 4x - 14 ) 

​e) 5y^10 + 15y^6

= 5y^6 (y^4 + 3 )

f) 9x^2y^2 + 15x^2y -21xy

 =  3xy( 3xy + 5x - 7)

g) x( y-1 ) - y ((y-1)

=(y -1) (x-y)

tách nhỏ câu hỏi ra bạn

\(a.10x\left(x-y\right)-6y\left(y-x\right)\\ =10x\left(x-y\right)+6y\left(x-y\right)\\ =\left(10x-6y\right)\left(x-y\right)\\ =2\left(5x-3y\right)\left(x-y\right)\)

\(b.14x^2y-21xy^2+28x^3y^2\\ =7xy\left(x-y+xy\right)\)

\(c.x^2-4+\left(x-2\right)^2\\ =\left(x-2\right)\left(x+2\right)+\left(x-2\right)^2\\ =\left(x-2\right)\left(x+2+x-2\right)\\ =2x\left(x-2\right)\)

\(d.\left(x+1\right)^2-25\\ =\left(x+1-5\right)\left(x+1+5\right)=\left(x-4\right)\left(x+6\right)\)

a,7xy(2x-3y+4xy)
b,(3x^2-5x)-(3xy-5y)
=x(3x-5)-y(3x-5)
=(3x-5)(x-y)

a: \(12x^3-6x^2+3x\)

\(=3x\cdot4x^2-3x\cdot2x+3x\cdot1\)

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

b: \(\dfrac{2}{5}x^2+5x^3+x^2y\)

\(=x^2\cdot\dfrac{2}{5}+x^2\cdot5x+x^2\cdot y\)

\(=x^2\left(\dfrac{2}{5}+5x+y\right)\)

c: \(14x^2y-21xy^2+28x^2y^2\)

\(=7xy\cdot2x-7xy\cdot3y+7xy\cdot4xy\)

\(=7xy\left(2x-3y+4xy\right)\)

\(14x^2y-21xy^2+28x^2y\)

\(=42x^2y-21xy^2\)

\(=21xy\left(2x-y\right)\)