`x^3+x^2+x=-1/3`
`<=>3x^3+3x^2+3x=-1`
`<=>x^3+3x^2+3x+1=-2x^3`
`<=>(x+1)^3=-2x^3`
`<=>x+1=-root{3}{2}x`
`<=>x(root{3}{2}+1)=-1`
`<=>x=-1/(root{3}{2}+1)`
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