Помогите срочно надо!№1x(x-3)(x-2)(x+1)=54

[latex]x(x-3)(x-2)(x+1)=54\\(x^2-3x)(x^2-x-2)=54\\x^4-4x^3+x^2+6x=54\\x^4-4x^3+x^2+6x-54=0\\(x^2-2x+6)(x^2-2x-9)=0\\\begin{cases}x^2-2x+6=0\;\;-\;\;D<0,\;pew.\;HET\\x^2-2x-9=0\end{cases}\\x^2-2x-9=0\\D=4+4\cdot9=40=\left(2\sqrt{10}\right)^2\\x_1=\frac{2-2\sqrt{10}}2=1-\sqrt{10}\\x_2=\frac{2+2\sqrt{10}}2=1+\sqrt{10}[/latex]