a) =2(a+b)

b) =2(a-2b)

c) =2(a+2b-3c)

d) =3(a-2b+3c)

e)= -4(a+2b+3c)

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

g) =-7(a+2ab+3b)

h) = 6(xy-2x-3y)

k) = 8(xy-3y+2x)

n)=9(ab-2a+1)

1, 2a+2b = 2( a + b )

2, 2a-2b = 2( a - b )

3, 2a+4b-6c = 2( a + 2b - 3c )

4, 3a-6b-9c = 3( a - 2b - 3c )

5, xy-x = x( y - 1 )

6, -5x-10xy-15y = -5( x + 2xy + 3y )

7, -7a-14ab-21b = -7( a + 2ab + 3b )

8, 6xy-12x-18y = 6 ( xy - 2x - 3y )

9, 8xy-24y+16x = 8 ( xy - 3y + 2x )

10, 9ab-18a+9 = 9( ab - 2a + 1 )

11, ax+a = a( x + 1 )

12, mx+my+m = m( x + y + 1 )

13, -ax-ay-a = -a( x + y +1 )

14, -2ax-4ay = -2a( x + 2y )

15, 2ax-2ay+2a = 2a( x - y + 1 )

16, 4ax-2ay-2 = 2( 2ax - a - 1 )

17, 5a-10ax-15a = 5a( 1 - 2x - 3 ) = 5a( -2x - 2 )

18, 5ax-15ay+20a = 5a( x - 3y + 4 )

19, 3a²x-6a²y+12a = 3a( ax - 2ay + 4 )

20, 2axy-4a²xy²+6a³x\(^2\) = 2ax( y - 2ay\(^2\) + 3a\(^2\)x )

1: 2a+2b=2(a+b)

2: 2a+4b+6c

=2*a+2*2b+2*3c

=2(a+2b+3c)

3: \(-7a-14ab-21b=-7\left(a+2ab+3b\right)\)

4: \(2ax-2ay+2a=2a\left(x-y+1\right)\)

5: \(=3a\cdot ax-3a\cdot2ay+3a\cdot4=3a\left(ax-2ay+4\right)\)

6: \(=2\cdot2ax-2\cdot ay-2\cdot1=2\cdot\left(2ax-ay-1\right)\)

7: =a^2-(2b)^2

=(a-2b)(a+2b)

8: =(5a)^2-1^2

=(5a-1)(5a+1)

9: =9(16a^2-9)

=9(4a-3)(4a+3)

1/ 2a + 2b = 2( a + b )

2/ 3a - 6b - 9c = 3( a - 2b - 3c )

3/ 5ax - 15ay + 20a = 5a( x - 3y + 4 )

4/ 3a²x - 6a²y + 12a = 3a( ax - 2ay + 4 )

5/ 4a( x - 5 ) - 2( 5 - x ) = 4a( x - 5 ) + 2( x - 5 ) = ( x - 5 )( 4a + 2 ) = ( x - 5 )2( 2a + 1 )

6. -3a( x - 3 ) + ( 3 - x ) = 3a( 3 - x ) + 1( 3 - x ) = ( 3a + 1 )( 3 - x )

7/ x^m+1 - x^m = x^m( x + 1 )

8/ x^m+2 - x² = x²( x^m - 1 ) 

a,(x+y)(2a-4)

b,(x+y)(a-b)

c,a(b+a)(x-5)

d,2a(a+2)(x+y)

**** cho mk nha

câu a ấy, làm chưa xong à?

a) 2a ( x + Y ) - 4 ( x + y )

= ( x + y ) ( 2a - 4)

b) x ( a - b ) - y ( b - a )

= x ( a - b ) +  y ( a - b)

= ( a - b ) ( x + y )

c) ab ( x - 5 ) - a^2 ( 5 - x )

= ab ( x - 5 ) + a^2 ( x - 5 )

= ( x - 5 ) ( ab + a^2 )

= ( x - 5 ) a ( b + a )

d) 2a^2 ( x - y) - 4a ( y - x )

= 2a^2 ( x - y ) + 4a ( x - y )

= ( x - y ) ( 2a^2 + 4a )

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

a) \(2a-4b=2\left(a-2b\right)\)

c) \(2ax-2ay+2a=2a\left(x-y+1\right)\)

e) \(3xy\left(x-4\right)-9x\left(4-x\right)=3x\left(x-4\right)\left(y+3\right)\)

b,d xem lại đề

b,d đúng mag bk

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

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

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

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

------------------------------------

\(a^3+3a^2-6a-8\)

\(=a^3+4a^2-a^2-4a-2a-8\)

\(=\left(a^3+4a^2\right)-\left(a^2+4a\right)-\left(2a+8\right)\)

\(=a^2\left(a+4\right)-a\left(a+4\right)-2\left(a+4\right)\)

\(=\left(a+4\right)\left(a^2-a-2\right)\)

\(=\left(a+4\right)\left(a^2-2a+a-2\right)\)

\(=\left(a+4\right)\left[\left(a^2-2a\right)+\left(a-2\right)\right]\)

\(=\left(a+4\right)\left[a\left(a-2\right)+\left(a-2\right)\right]\)

\(=\left(a+4\right)\left(a-2\right)\left(a+1\right)\)

---------------------------------

\(2x^2-5x+2\)

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

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

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

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

-----------------------------------------

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

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

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

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

-------------------------------------

\(a^2-1+4b-4b^2\)

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

\(=a^2-\left(1-2b\right)^2\)

\(=\left(a-1+2b\right)\left(a+1-2b\right)\)

----------------------------------------

\(a^4+6a^2b+9b^2-1\)

\(=\left(a^4+6a^2b+9b^2\right)-1\)

\(=\left(a^2+3b\right)^2-1\)

\(=\left(a^2+3b-1\right)\left(a^2+3b+1\right)\)

---------------------------------

\(2x^3+16y^3\)

\(=2\left(x^3+8y^3\right)\)

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

Lần sau ghi đề tách riêng từng câu ra nhé em. Ghi dính chùm vậy khó nhìn lắm. Sẽ ít ai giải cho em