\(9x^6-12x^7+4x^8\)

\(=9x^6-6x^7-6x^7+4x^8\)

\(=3x^6\left(3-2x\right)-2x^7\left(3-2x\right)\)

\(=3x^6\left(3-2x\right)-2x^7\left(3-2x\right)\)

\(=\left(3-2x\right)\left(3x^6-2x^7\right)\)

\(=x^6\left(3-2x\right)\left(3-2x\right)=x^6.\left(3-2x\right)^2\)

a: \(x^3-2x+4\)

\(=x^3+2x^2-2x^2-4x+2x+4\)

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

b: \(x^3-4x^2+12x-27\)

\(=\left(x-3\right)\left(x^2+3x+9\right)-4x\left(x-3\right)\)

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

c: \(x^3+2x^2+2x+1\)

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

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

\(27y^3-9y^2+y-\frac{1}{27}\)

\(=\left(3y\right)^3-3.\left(3y\right)^2.\frac{1}{3}+3.3y.\left(\frac{1}{3}\right)^2-\left(\frac{1}{3}\right)^3\)

\(=\left(3y-\frac{1}{3}\right)^3\)

hk

tốt

\(x^4-x^2+2x-1\)

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

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

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

hk

tốt

( a + b )³ - ( a³ + b³ )

= a³ + 3a²b + 3ab² + b³ - a³ - b³

= 3a²b - 3ab²

= 3ab ( a + b )

\(\left(a+b\right)^3-\left(a^3+b^3\right)\)

\(=\left(a+b\right)^3-\left(a+b\right)\left(a^2-ab+b^2\right)\)

\(=\left(a+b\right)\left(a^2+2ab+b^2-a^2+ab-b^2\right)\)

\(=3ab\left(a+b\right)\)

Phân tích các đa thức sau thành nhân tử:

(a+b)^3-(a^3+b^3) = 3a . b . (b+a)

nha bạn chúc bạn học tốt nha 

:)))))))))

cái này có những biểu thức ko dùng được hđt hoặc đặt nhân tử chung =))) anh nghĩ đề em nên thay chữ và thành hoặc 

1, \(15x^2+10xy=5x\left(3x+2y\right)\)

2, \(24x-18y+30=6\left(4x-3y+5\right)\)

3, \(2x\left(y-2009\right)+5y\left(y-2009\right)=\left(y-2009\right)\left(2x+5y\right)\)

4, \(35x\left(y-8\right)-14y\left(8-y\right)=\left(y-8\right)\left(35x+14y\right)=7\left(5x+2y\right)\left(y-8\right)\)

5, \(x^2+14x+49=x^2+2.7x+7^2=\left(x+7\right)^2\)

6, \(9x^2-4=\left(3x-2\right)\left(3x+2\right)\)

Trả lời:

1, 15x² + 10xy = 5x ( 3x + 2y )

2, 24x - 18y + 30 = 6 ( 4x - 3y + 5 )

3, 2x ( y - 2009 ) + 5y ( y - 2009 ) = ( y - 2009 )( 2x + 5y )

4, 35x ( y - 8 ) - 14y ( 8 - y ) = 35x ( y - 8 ) + 14y ( y - 8 ) = ( y - 8 )( 35x + 14y ) = 7 ( y - 8 )( 5x + 2y )

5, x² + 14x + 49 = ( x + 7 )² 

6, 9x² - 4 = ( 3x - 2 )( 3x + 2 )

a) \(=\left(x-2\right)^2\)

b) \(=\left(2x+1\right)^2\)

c) \(=\left(4x-3y\right)\left(4x+3y\right)\)

d) \(=\left(4-x-3\right)\left(4+x+3\right)=\left(1-x\right)\left(x+7\right)\)

e) \(=\left(2x-3x+1\right)\left(2x+3x-1\right)=\left(1-x\right)\left(5x-1\right)\)

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

g) \(=\left(x+3\right)\left(x^2-3x+9\right)\)

h) \(=\left(x+2\right)^3\)

i) \(=\left(1-x\right)^3\)

a/ $=(x-2)^2$

b/ $=(2x+1)^2$

c/ $=(4x-3y)(4x+3y)$

d/ $=(1-x)(x+7)$

e/ $=(-x+1)(5x-1)$

f/ $=(x-y)(x^2+xy+y^2)$

g/ $=(3+x)(9-3x+x^2)$

h/ $=(x+2)^3$

i/ $=(1-x)^3$

a: \(x^2-4x+4=\left(x-2\right)^2\)

b: \(4x^2+4x+1=\left(2x+1\right)^2\)

g: \(x^3+27=\left(x+3\right)\left(x^2-3x+9\right)\)

\(=-2x^2+6xy-3y^2+25\)

\(=-\left(2x^2-6xy+3y^2\right)+25\)

\(=-\left(2x^2+3y^2\right)+25\)

\(=\left(2x^2-3y^2\right)+25\)

\(=\left(2x^2+3y^2\right).\left(2x^2-3y^2\right)+25\)

quên rùi

\(-4x^2+12xy-9y^2+25=\left(-4x^2+6xy+10x\right)+\left(6xy-9y^2-15y\right)-\left(10x-15y-25\right)\)

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

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