info prev up next book cdrom email home

de Moivre Number

A solution $\zeta_k=e^{2\pi i k/d}$ to the Cyclotomic Equation

\begin{displaymath}
x^d=1.
\end{displaymath}

The de Moivre numbers give the coordinates in the Complex Plane of the Vertices of a regular Polygon with $d$ sides and unit Radius.
$n$ de Moivre Number
2 $\pm 1$
3 1, ${\textstyle{1\over 2}}(-1\pm i\sqrt{3}\,)$
4 $\pm 1, \pm i$
5 1, ${1\over 4}(-1+\sqrt{5}\pm i\sqrt{10+2\sqrt{5}}\,)$, ${\textstyle{1\over 4}}(-1-\sqrt{5}\pm i\sqrt{10-2\sqrt{5}}\,)$
6 $\pm 1, \pm{\textstyle{1\over 2}}(\pm 1+i\sqrt{3}\,)$

See also Cyclotomic Equation, Cyclotomic Polynomial, Euclidean Number


References

Conway, J. H. and Guy, R. K. The Book of Numbers. New York: Springer-Verlag, 1996.




© 1996-9 Eric W. Weisstein
1999-05-24