Question

Phân tích đa thức thành nhân tử :

1)\(12x^3-43x^2-20x+3\)

2)\(x^3+4x^2-11x-30\)

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

Answer 1

1) 12x³ - 43x² - 20x +3

= x( 12x²- 43x -20 ) + 3

=x[x(12x-43-20]+3

=x[x(12x-63)]+3

2) x³+4x²-11x-30

= x(x²+4x-11)-30

= x[x(x+4-11)]-30

= x[x(x-7)] - 30

3) x³+3x²-2

= x²(x+3)-2

Answer 2

2: \(=x^3-3x^2+7x^2-21x+10x-30\)

\(=\left(x-3\right)\left(x^2+7x+10\right)\)

\(=\left(x-3\right)\left(x+2\right)\left(x+5\right)\)

3: \(=x^3+x^2+2x^2-2\)

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

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