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

b) \(11\left(x+y\right)-x\left(x+y\right)=\left(x+y\right)\left(11-x\right)\)

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

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

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

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

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

b) \(\left(x+2\right)^2-9=\left(x-1\right)\left(x+5\right)\)

c) \(\left(a+b\right)^2-\left(a-2b\right)^2\)

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

\(=3b\left(2a-b\right)\)

`a, 4x^2-1 = (2x+1)(2x-1)`

`b, (x+2)^2-9 = (x+2-3)(x+2+3) = (x-1)(x+5)`

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

`a, 4a^2 + 4a + 1 = (2a+1)^2`

`b, -3x^2 + 6xy - 3y^2`

` = -3(x-y)^2`

`c, (x+y)^2 - 2(x+y)z + z^2`

`= (x+y-z)^2`

`a, x^3 + 4x = x(x^2+4)`

`b, 6ab - 9ab^2 = 3ab(2-b)`

`c, 2a(x-1) + 3b(1-x)`

`= (2a-3b)(x-1)`

`d, (x-y)^2 - x(y-x)`

`= (x-y+x)(x-y)`

`= (2x-y)(x-y)`

a) \(x^2-xy+x-y\)

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

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

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

b) \(x^2+2xy-4x-8y\)

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

\(\left(x-4\right)\left(x+2y\right)\)

c) \(x^3-x^2-x+1\)

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

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

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

4a²b²-(a²+b²-c²)²

= (4ab-a²-b²+c²)(4ab+a²+b²-c²)

= -[(a-b)²-c²][(a+b)²-c²]

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

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

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

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

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

a) \(=5x\left(x-2\right)\)

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

1/
a) 3x²

a) \(3x^2\left(2x-1\right)=6x^3-3x^2.\)

a) \(5x^2-10x=5x\left(x-2\right).\)

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

`a)7x^3y^2+14x^2y^3+7xy^4`

`=7xy^2(x^2+2xy+y^2)`

`=7xy^2(x+y)^2`

______________________________________________

`b)x^2-xy+5x-5y`

`=x(x-y)+5(x-y)`

`=(x-y)(x+5)`

______________________________________________

`c)3x^2-6xy-12+3y^2`

`=3(x^2-2xy-4+y^2)`

`=3[(x-y)^2-4]`

`=3(x-y-2)(x-y+2)`

a)7x³y²+14x²y³+7xy⁴

=7xy²(x²+2xy+y²)

=7xy²(x+y)²

b)x²-xy + 5x - 5y

=x(x-y) + 5(x-y)

=(x-y) (x+5)

p

Lời giải:

a. 

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

$=xy(xy+1)-2(xy+1)=(xy+1)(xy-2)$

b. Bạn xem lại đoạn $-16x^2$ là dấu - hay + vậy?