New posts in Abstract Algebra

Given that $\cos\left(\dfrac{2\pi m}{n}\right) \in \mathbb{Q}$ prove $\cos\left(\dfrac{2\pi}{n}\right) \in \mathbb{Q}$

Ideal of height $>1$ containing no non-zero prime ideals.

Concrete Bezout's Theorem Calculation

Does the short exact sequence $0\mapsto \mathbb{Z}^k\mapsto \Gamma\mapsto \mathbb{Z}^\ell\mapsto 0$ split?

Questions about Definition of Vector Spaces

A surjective homomorphism which is not an isomorphism for rings (Using basic algebra)

Number of elements of order $n$: explain why $\Bbb{Z}_4\times\Bbb{Z}_4$ and $\Bbb{Z}_4\times\Bbb{Z}_2\times\Bbb{Z}_2$ are not isomorphic.

Completeness of a quantifier-free axiomatization of Boolean algebra using partial-ordering

Example to show that $\mathbb Z^3$ is not a quotient of $\mathbb Z[X]$

Is every injective ring homomorphism an automorphism?