Question

Phân tích đa thức sau thành nhân tử:

\(\text{x}^{\text{4}}+5\text{x}^{\text{3}}-7\text{x}^{\text{2}}-41x-30\)

Answer 1

\(=x^4+6x^3+5x^2-x^3-6x^2-5x-6x^2-36x-30\)

\(=x^2\left(x^2+6x+5\right)-x\left(x^2+6x+5\right)-6\left(x^2+6x+5\right)\)

\(=\left(x^2-x-6\right)\left(x^2+6x+5\right)\)

\(=\left(x-3\right)\left(x+2\right)\left(x+1\right)\left(x+5\right)\)