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How to find the root of $x^4 +1$

What algorithms can be used for finding all roots of the given polynomial:

\begin{equation} x^4 + 1 = 0 \end{equation}

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    It depends somewhat on what you mean by "find" -- if the end result of 'finding' is the phrase "they are the primitive eighth roots of unity", is that good enough?2012-12-22
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    You get this factorization almost instantaneously if you know that multiplication by a non-zero complex number consists of rotating and dilating. Use that to find fourth roots of $-1$.2012-12-22

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