Question

x³ -6x -x +30

Answer 1

\(x^3-6x^2-x+30=\left(x^3-8x^2+15x\right)+\left(2x^2-16x+30\right)\)

\(=x\left(x^2-8x+15\right)+2\left(x^2-8x+15\right)\)

\(=\left(x+2\right)\left(x^2-8x+15\right)\)

\(=\left(x+2\right)\left(x^2-3x-5x+15\right)\)

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

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

Answer 2

Em xem lại đề, \(-6x\) hay \(-6x^2\)