Question

[Ngô Ngọc Ánh]

Phân tích đa thức thành nhân tử:

a/\(x^2+7x+6\)

b/\(x^2+2008x^2+2007x+2008\)

E đg cần gấp

Answer 1

[Ngô Chi Lan]

a.\(x^2+7x+6\)

\(=x^2+x+6x+6\)

\(=x\left(x+1\right)+6\left(x+1\right)\)

\(=\left(x+1\right)\left(x+6\right)\)

Sửa đề:.\(x^4+2008x^2+2007x+2008\)

\(=x^4+x^2+1+2007x^2+2007x+2007\)

\(=\left(x^4+x^2+1\right)+2007\left(x^2+x+1\right)\)

\(=\left(x^4+x^3+x^2-x^3-x^2-x+x^2+x+1\right)+2007\left(x^2+x+1\right)\)

\(=\left[x^2\left(x^2+x+1\right)-x\left(x^2+x+1\right)+\left(x^2+x+1\right)\right]+2007\left(x^2+x+1\right)\)

\(=\left(x^2+x+1\right)\left(x^2-x+1\right)+2007\left(x^2+x+1\right)\)

\(=\left(x^2+x+1\right)\left(x^2-x+2008\right)\)

Answer 2

[Quỳnh Anh]

Trả lời:

a, x² + 7x + 6

= x² + x + 6x + 6

= ( x² + x ) + ( 6x + 6 )

= x ( x + 1 ) + 6 ( x + 1 )

= ( x + 6 ) ( x + 1 )