Bài 17 :

1) ab + ac = a ( b + c )

2) ab  - ac + ad = a ( b - c + d )

3) ax - bx - cx + dx = x ( a- b - c + d )

4) a(b + c) – d(b + c) = ( b + c ) ( a - d )

5) ac – ad + bc – bd = a( c - d ) + b ( c - d ) = ( c- d ) ( a + b )

6) ax + by + bx + ay = a( x+ y ) + b ( x + y ) = ( x + y ) (a +b )

Bài 18:

1/ (a – b + c) – (a + c) = a - b + c - a - c = -b

2/ (a + b) – (b – a) + c = a + b - b + a + c = 2a + 2

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

4/ a(b + c) – a(b + d) = a ( b + c - b - d ) = a( c - d )

5/ a(b – c) + a(d + c) = a ( b - c + d + c ) = a ( b+ d ) 

Bài 1

1,ab+ac=a.(b+c)

2,ab-ac+ad=a.(b-c+d)

3,ax-bx-cx+dx=x.(a-b-c+d)

4,a.(b+c)-b.(b+c)=(b+c).(a-b)

5,ac-ad+bc-bd=a.(c-d)+b.(c-d)=(c-d).(a+b)

6,ax+by+bx+ay=a.(x+y)+b.(x+y)=(x+y).(a+b)

Bài 2

1,(a-b+c)-(a+c)=-b

 =a-b+c-a-c

 =(a-a)+(c-c)-b

 =0+0-b

 =-b

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

 =a+b-b+a+c

 =(a+a)+(b-b)+c

 =2a+0+c

 =2a+c

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

 =-a-b+c+a-b-c

 =(-a-a)+[-b+(-b)]+(c-c)

 =0+(-2b)+0

 =-2b

4,a.(b+c)-a.(d+c)=a.(c-d)

   =ab+ac-ab-ad

   =a.(b+c-b-d)

   =a.(c-d)

5,a.(b-c)+a.(d+c)=a.(b+d)

  =ab-ac+ac+ad

  =a.(b-c+c+d)

  =a.(b+d)

ĐẶT NHÂN TỬ CHUNG NHA!

1) ab - ac + ad = a( b- c +d ) 

2) ax - bx - cx + dx = x( a-b-c+d)

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

4) ac - ad + bc - bd = a( c-d)  + b( c-d) = (a+b)(c-d)

5) ax + by + bx + ay= a( x+y) + b( x+y) = (a+b)(x+y)

1) ab + ac = a(b + c)

2) ab - ac + ad = a(b - c + d)

3) ax - bx - cx + dx = x(a - b - c + d)

4) a(b + c) - d(b + c) = (b + c)(a - d)

5) ac - ad + bc - bd = a(c - d) + b(c - d) = (c - d)(a + b)

6) ax + by + bx + ay = (ax + ay) + (bx + by) = a(x + y) + b(x + y) = (x + y)(a + b)

ab + ac = a ( b + c )

ab - ac + ad = a ( b - c + d )

ax - bx - cx + dx = x ( a - b - c + d )

1/ab+ac=a(b+c)

2/ab-ac+ad=a(b-c)+ad=a(b-c+d)

3/ax-bx-cx+dx=x(a-b-c)+xd=x(a-b-c+d)

4/a(b+c)-d(b+c)=(ab+ac)-(bd+cd)=b(a+d)-c(a+d)=a+d(b+c)

5/ac-ad+bc-bd=a(c-d)+b(c-d)=c-d(a+b)

6/ax+by+bx+ay=a(x+y)+b(x+y)=x+y(a+b)

1/ ab+ac=a(b+c)

2/ab-ac+ad=a(b-c+d)

3/ax-bx-cx+dx=x(a-b-c+d)

4/a(b+c)-d(b+c)=(b+c)(a-d)

5/ac-ad+bc-bd=a(c-d)+b(c-d)=(c-d)(a+b)

6/ax+by+bx+ay=a(x+y)+b(y+x)=(y+x)(a+b)

\(1,ab+ac\)

\(=a\left(b+c\right)\)

\(2,ab-ac+ad\)

\(=a\left(b-c+d\right)\)

\(3,ax-bx-cx+dx\)

\(=x\left(a-b-c+d\right)\)

\(4,a\left(b+c\right)-d\left(b+c\right)\)

\(=\left(b+c\right)\left(a-d\right)\)

\(5,ac-ad+bc-bd\)

\(=a\left(c-d\right)+b\left(c-d\right)\)

\(=\left(a+b\right)\left(c-d\right)\)

\(6,ax+by+bx+ay\)

\(=\left(ax+bx\right)+\left(by+ay\right)\)

\(=x\left(a+b\right)+y\left(a+b\right)\)

\(=\left(x+y\right)\left(a+b\right)\)

1? 

a(b+c)

a(b-c+d)

x(a-b-c+d)

(b+c)(a-d)

(c-d)(a+b)

(x+-y)(a+b)

1/ ab+ ac

=a(b+c)

2/ ab - ac + ad

=a(b-c+d)

3/ ax - bx - cx + dx

=x(a-b-c+d)

4/ a(b + c) - d(b + c)

=(a-d)(b+c)

5/ ac - ad + bc - bd

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

=(a+b)(c-d)

6/ ax + by + bx + ay

=x(a+b)+y(b+a)

=(x+y)(b+a)

A) ab + ac=a.(b+c)

B)ab - ac + ad=a.(b-c+d)

C) ã-bx-cx+dx=x.(a-b-c+d)

D)a(b+c) - d(b+c)=(b+c).(a-d)

E) ac-ad+bc-bd=a.(c-d)+b.(c-d)=(c-d).(a+b)

G) ax+by+bx+ay=x.(a+b)+y.(b+a)=(a+b).((x.y)

1) \(ab+ac=a\left(b+c\right)\)

2) \(ab-ac+ad=a\left(b-c+d\right)\)

3) \(ax-bx-cx+dx=x\left(a-b-c+d\right)\)

4) \(a\left(b+c\right)-d\left(b+c\right)=\left(b+c\right)\left(a-d\right)\)

5) \(ac-ad+bc-bd=a\left(c-d\right)+b\left(c-d\right)=\left(a+d\right)\left(c-d\right)\)

6) \(ax+by+bx+ay=x\left(a+b\right)+y\left(a+b\right)=\left(x+y\right)\left(a+b\right)\)

1, ab + ac = a(b+c)

2, ab - ac + ad = a(b-c+d)

3, ax-bx-cx+dx = x(a-b-c+d)

4, a(b+c) - d(b+c) = (a-d)(b+c)

5, ac-ad+bc-bd = a(c-d) + b(c-d) = (a+b)(c-d)

6, ax+by+bx+ay=ax+ay+bx+by=a(x+y)+b(x+y)=(a+b)(x+y)

a(b+c)
a(b-c+d)
x(a-b-c+d)
(b+c)(a-d)
a(c-d)+c(c-d)=(c-d)(a+c)
a(x+y)+b(x+y)=(x+y)(a+b)
T

1 .  a(a+b)

2 .    a(b-c+d)

2   .  x(a-b-c+d)

4  (b+c)(a-d)

5   ac-d) + b(c-d)  = (c-d)(a+b)

6  x(a+b)+y(a+b)= (a+b)(x+y)

1/ a(b+c)

2/ a(b-c+d)

3/ x(a-b-c+d)

4/ (a-d)(b+c)

5/ (a+b)(c-d)

6/ (a+b)(x+y)