\(x^3-9x^2+6x+16=x^3-8x^2-x^2+8x-2x+16\)
\(=x^2.\left(x-8\right)-x.\left(x-8\right)-2.\left(x-8\right)\)
\(=\left(x-8\right).\left(x^2-x-2\right)=\left(x-8\right).\left(x^2-2x+x-2\right)\)
\(=\left(x+8\right)\left[x.\left(x-2\right)+\left(x-2\right)\right]\)
\(=\left(x+8\right).\left(x-2\right)\left(x+1\right)\)
\(x^3-9x^2+6x+16\)
\(=\left(x^3+x^2\right)-\left(10x^2+10x\right)+\left(16x+16\right)\)
\(=x^2.\left(x+1\right)-10x\left(x+1\right)+16\left(x+1\right)\)
\(=\left(x+1\right)\left(x^2-10x+16\right)\)
Tham khảo nhé~
\(x^3-9x^2+6x+16\)
\(=x^3+x^2-10x^2-10x+16x+16\)
\(=x^2\left(x+1\right)-10x\left(x+1\right)+16\left(x+1\right)\)
\(=\left(x+1\right)\left(x^2-10x+16\right)\)
\(=\left(x+1\right)\left[x^2-2x-8x+16\right]\)
\(=\left(x+1\right)\left[x\left(x-2\right)-8\left(x-2\right)\right]\)
\(=\left(x+1\right)\left(x-2\right)\left(x-8\right)\)
Chúc bạn học tốt.
