Question

Phân tích thành nhân tử:

 a) x³+2x²+x-4xy²

b) x³+4x²-12x-27

c) x²+x-12

Answer 1

\(x^3+2x^2+x-4xy^2\)

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

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

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

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

Answer 2

\(\text{x3+2x2+x−4xy2 =x(x2+2x+1)−4xy2 =x(x+1)2−4xy2 =x((x+1)2−4y2) =x((x+1−2y)(x+1+2y))}\)

Answer 3

b)

x³-3x²+7x²-21x+9x-27

=x²(x-3)+7x(x-3)+9(x-3)

=(x-3)(x²+7x+9)

Answer 4

c) =x²-3x+4x-12

=x(x-3)+4(x-3)

=(x-3)(x+4)