\( \DeclareMathOperator{\abs}{abs} \newcommand{\ensuremath}[1]{\mbox{$#1$}} \)
(%i1) load(odes)$
(%i2) eq: -x^6 +x^5 +2*x^4 -2*x^3 +x^2 +2*x -1 = 0;
\[\tag{eq}\label{eq}-{{x}^{6}}+{{x}^{5}}+2{{x}^{4}}-2{{x}^{3}}+{{x}^{2}}+2x-1=0\]
(%i3) solvet(eq,x);
\[\tag{\%{}o3}\label{o3} [x=-1,x=-\frac{\sqrt{3}\%{}i-1}{2},x=\frac{\sqrt{3}\%{}i+1}{2},x=\frac{2\sqrt{7}\,\cos{\left( \frac{\operatorname{atan}\left( {{3}^{\frac{3}{2}}}\right) -3\ensuremath{\pi} }{3}\right) }+1}{3},x=\frac{2\sqrt{7}\,\cos{\left( \frac{\operatorname{atan}\left( {{3}^{\frac{3}{2}}}\right) -\ensuremath{\pi} }{3}\right) }+1}{3},x=\frac{2\sqrt{7}\,\cos{\left( \frac{\operatorname{atan}\left( {{3}^{\frac{3}{2}}}\right) +\ensuremath{\pi} }{3}\right) }+1}{3}]\]
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