Ta có: \(1+6x-6x^2-x^3\)

\(=-x^3-6x^2+6x+1\)

\(=\left(-x^3+1\right)-6x\left(x-1\right)\)

\(=-\left(x-1\right)\left(x^2+x+1\right)-6x\cdot\left(x-1\right)\)

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

\(=-\left(x-1\right)\left(x^2+7x+1\right)\)

\(1+6x-6x^2-x^3\)

= (1-x^3)+(6x-6x^2)

=(1-x)(1+x+x^2)+6x(1-x)

=(1-x)( 1+ x+ x^2 + 6x)

=(1-x)(1+x^2 +7x)

Đây bạn ơi!

1)

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

2)

\(8x^3-12x^2+6x-2\\ =2\left(4x^3-6x^2+3x-1\right)\\ =2\left(4x^3-4x^2-2x^2+2x+x-1\right)\\ =2\left(4x^2\left(x-1\right)-2x\left(x-1\right)+\left(x-1\right)\right)\\ =2\left(x-1\right)\left(4x^2-2x+1\right)\)

1) \(y^2-4y+4-x^2\)

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

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

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

2) \(8x^3-12x^2+6x-1\)

\(=\left(2x\right)^3-3\cdot\left(2x\right)^2\cdot1+3\cdot2x\cdot1^2-1^3\)

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

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

1. \(=3x\left(2x+5\right)\)

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

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

1, = 3x.(2x + 5)

2. = (3x)² - 1² = (3x - 1).(3x +1 )

3, =(x² + 6x + 9) - y² = (x + 3)² - y² =(x + y -3 ). (x - y +3)

3.\(x^2+6x-y^2+9=\left(x^2+6x+9\right)-y^2=\left(x+3\right)^2-y^2=\left(x+3-y\right)\left(x+3+y\right)\)

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

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

3: \(x^2+7x+12=\left(x+3\right)\left(x+4\right)\)

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

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

3) \(x^2+7x+12=\left(x^2+3x\right)+\left(4x+12\right)=x\left(x+3\right)+4\left(x+3\right)=\left(x+3\right)\left(x+4\right)\)

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

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

3: \(x^2+7x+12=\left(x+3\right)\left(x+4\right)\)

1, \(12x^2+7x-12=12x^2+16x-9x-12=\left(3x+4\right)\left(4x-3\right)\)

2, \(2m^2+10m+8=2m^2+2m+8m+8=\left(2m+8\right)\left(m+1\right)\)

\(12x^2+7x-12=12x^2-9x+16x-12\)

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

\(2m^2+10m+8=2m^2+2m+8m+8\)

\(=2m\left(m+1\right)+8\left(m+1\right)=2\left(m+4\right)\left(m+1\right)\)

\(1.12x^2+7x-12=\left(4x-3\right)\left(3x+4\right)\\ 2.2m^2+10m+8=2\left(m+1\right)\left(m+4\right)\)

\(\dfrac{1}{2}x^3+4\)

\(=\dfrac{1}{2}\left(x^3+8\right)\)

\(=\dfrac{1}{2}\left(x^3+2^3\right)\)

\(=\dfrac{1}{2}\left(x+2\right)\left(x^2-2\cdot x+2^2\right)\)

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

=1/2(x^3+8)

=1/2(x+2)(x^2-2x+4)

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

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

\(x^2+2xy-15y^2=x^2-3xy+5xy-15y^2=x\left(x-3y\right)+5y\left(x-3y\right)=\left(x+5y\right)\left(x-3y\right)\)

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

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

3: \(x^2+2xy-15y^2=\left(x+5y\right)\left(x-3y\right)\)

\(1,x^2-16y^2=\left(x-4y\right)\left(x+4y\right)\)

\(2,21x-21y+ax-ay=21\left(x-y\right)+a\left(x-y\right)=\left(21+a\right)\left(x-y\right)\)

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