Roots of Unity

1 min read Last updated Mon Jun 01 2026 03:58:53 GMT+0000 (Coordinated Universal Time)

nn-th roots of unity (11) are the complex numbers that satisfy the equation, zn=1z^n = 1. There are nn distinct solutions.

z=exp(i(2mπn))    where    mZ[0,n)={0,1,,n1}z = \exp\bigg({i\Big(\frac{2m\pi}{n}\Big)}\bigg) \;\; \text{where} \;\; m\in \mathbb{Z}\cap[0,n) = \set{ 0, 1, \dots, n-1 }

The solution can be written as 1,w,w2,w3,,wn11, w, w^2, w^3, \dots, w^{n-1}. 11 is the trivial solution.

An nn-th root is primitive iff it is not an mm-th root of unity for m<nm \lt n. If nn is a prime number, then all nnth roots of unity except 1, are primitive.

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