\(x^3-x^2-14x+24\)

\(=x^3+4x^2-5x^2-20x+6x+24\)

\(=\left(x^3+4x^2\right)-\left(5x^2+20x\right)+\left(6x+24\right)\)

\(=x^2\left(x+4\right)-5x\left(x+4\right)+6\left(x+4\right)\)

\(=\left(x^2-5x+6\right)\left(x+4\right)\)

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

\(=\left[x\left(x-2\right)-3\left(x-2\right)\right]\left(x+4\right)\)

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

x(y+z)^2 - y(z-x)^2 +z(x+y)^2 - x^3 + y^3 - z^3 - 4xyz

=xy^2+2xyz+xz^2-yz^2+2xyz-x^2y+x^2z+2xyz+zy^2-x^3+y^3-z^3-4xyz

=xy^2+xz^2-yz^2-x^2y+x^2z+y^2z-x^3+y^3-z^3+2xyz

=(xy^2+2xyz+xz^2)-x^3-(yz^2+2xyz+x^2y)+y^3+(x^2z+2xyz+y^2z)-z^3

=x[(y+z)^2-x^2)-y[(z+x)^2-y^2]+z[(x+y)^2-z^2]

=x(-x+y+z)(x+y+z)-y(x-y+z)(x+y+z)+z(x+y-z)(x+y+z)

=(x+y+z)[-x^2+xy+xz-xy+y^2-yz+xz+yz-z^2]

=(x+y+z)[-x(x-y-z)-y(x-y-z)+z(x-y-z)]

=(x+y+z)(x-y-z)(z-x-y)

\(x-\sqrt{x}-2\\ =x+\sqrt{x}-2\sqrt{x}-2\\ =\sqrt{x}\left(\sqrt{x}+1\right)-2\left(\sqrt{x}+1\right)\\ =\left(\sqrt{x}+1\right)\left(\sqrt{x}-2\right)\)

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mk chưa lên lp 8

a) \(27x^3+27x^2+9x+1=\left(3x+1\right)^3\)

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

c) \(-8+12x-6x^2+x^3=\left(x-2\right)^3\)

=x¹¹-x²+x²+x+1

=x²(x⁹-1)+(x²+x+1)

=x²[(x³)³-1³)+(x²+x+1)

=x²(x³-1)(x⁶+x³+1)+(x²+x+1)

=x²(x⁶+x³+1)(x-1)(x²+x+1)+(x²+x+1)

Đặt nhân tử chung là x²+x+1 rồi phá hết ngoặc là xong