New posts in roots-of-unity

Concurrent lines proof for a regular 18-gon

geometry complex-numbers roots-of-unity

Find all five solutions of the equation $z^5+z^4+z^3+z^2+z+1 = 0$

complex-analysis complex-numbers roots roots-of-unity

Determine splitting field $K$ over $\mathbb{Q}$ of the polynomial $x^3 - 2$

field-theory irreducible-polynomials roots-of-unity splitting-field

Show that $\mathbb{Q}(\zeta_n)$ is Galois over $\mathbb{Q}$ and $Gal(\mathbb{Q}(\zeta_n)/\mathbb{Q}))\cong \mathbb{Z_n}^*$ [duplicate]

field-theory galois-theory extension-field roots-of-unity cyclotomic-fields

Inverse Limits: Isomorphism between Gal$(\mathbb{Q}(\cup_{n \geq 1}\mu_n)/\mathbb{Q})$ and $\varprojlim (\mathbb{Z}/n\mathbb{Z})^\times$

galois-theory roots-of-unity

Solutions of $x^2 \equiv 1 \pmod N$

modular-arithmetic roots-of-unity quadratic-residues

Question on primitive roots of unity

abstract-algebra roots-of-unity

Problem based on sum of reciprocal of $n^{th}$ roots of unity

algebra-precalculus roots-of-unity

Drunkard's walk on the $n^{th}$ roots of unity.

probability stochastic-processes markov-chains roots-of-unity

A spiralling sequence based on integer divisors. Has anyone noticed this before?

sequences-and-series complex-numbers prime-numbers divisibility roots-of-unity

Sum of nth roots of unity

complex-analysis complex-numbers summation roots-of-unity

Intuitive understanding of why the sum of nth roots of unity is $0$

number-theory intuition roots-of-unity

Prove that $\cot^2{(\pi/7)} + \cot^2{(2\pi/7)} + \cot^2{(3\pi/7)} = 5$

trigonometry proof-writing roots-of-unity

On the trigonometric roots of a cubic

trigonometry roots closed-form roots-of-unity cubics

Is $\sqrt 7$ the sum of roots of unity?

roots-of-unity

Prove that $\prod_{k=1}^{n-1}\sin\frac{k \pi}{n} = \frac{n}{2^{n-1}}$

trigonometry complex-numbers products roots-of-unity