Question

phân tích đa thức thành nhân tử :

a) 3x^3-7x^2-17x-5

b)4x^3-13x^2+9x-18

Answer 1

\(4x^3-13x^2+9x-18=4x^3-12x^2-x^2+3x+6x-18\)

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

Answer 2

\(4x^3-13x^2+9x-18\)

\(=4x^3-12x^2-x^2+3x+6x-18\)

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

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