Question 782038
{{{ x^6 - 4x^3 - 480 = 0 }}}
{{{ z^2 = x^6 }}}
{{{ z = x^3 }}}
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{{{ z^2 - 4z - 480 = 0 }}}
{{{ z^2 - 4z + (4/2)^2 = 480 + (4/2)^2 }}}
{{{ z^2 - 4z + 4 = 484 }}}
{{{ ( z - 2 )^2 = 22^2 }}}
{{{ z - 2 = 22 }}}
{{{ z = 24 }}}
also
{{{ z - 2 = -22 }}}
{{{ z = -20 }}}
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{{{ z = x^3 }}}
{{{ x^3 = 24 }}}
{{{ x^3 = -20 }}}
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{{{ x = 24^(1/3) }}}
{{{ x = (-20)^(1/3) }}}
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{{{ x = 2*root(3,3) }}}
{{{ x = -2*3^(-1/6) + 3^(5/6)*i }}}
{{{ x = -2*3^(-1/6) - 3^(5/6)*i }}}
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{{{ x = root(3,-20) }}}
{{{ x = -root(3,-20)/ sqrt(3) + 2*root(3,-20)/ sqrt(3) }}}
{{{ x = -root(3,-20)/ sqrt(3) - 2*root(3,-20)/ sqrt(3) }}}