Đáp án:
\(=\left(x+1\right).\left(x+2\right).\left(x-3\right)\)
Giải thích các bước giải:
`x^3 - 7x - 6`
\(x^3-7x-6=x^3+x^2-x^2-x-6x-6\)
\(=\left(x^3+x^2\right)-\left(x^2+x\right)-\left(6x+6\right)\)
\(=x^2.\left(x+1\right)-x.\left(x+1\right)-6.\left(x+1\right)\)
\(=\left(x+1\right).\left(x^2-x-6\right)\)
\(=\left(x+1\right).\left(x^2+2x-3x-6\right)\)
\(=\left(x+1\right).\left[\left(x^2+2x\right)-\left(3x+6\right)\right]\)
\(=\left(x+1\right).\left[x.\left(x+2\right)-3.\left(x+2\right)\right]\)
\(=\left(x+1\right).\left(x+2\right).\left(x-3\right)\)
