1 day ago · Mathematics Stack Exchange is a platform for asking and answering questions on mathematics at all levels.

Jun 4, 2012 · A remark: regardless of whether it is true that an infinite union or intersection of open sets is open, when you have a property that holds for every finite collection of sets (in this case, the union …

Estoy haciendo mi reciente evaluación interna del IB Matemáticas HL y mi tema es cómo calcular el área de superficie de un huevo . Quiero aplicar el cálculo conocimiento en esta pregunta, pero mi …

Prove that that $U(n)$, which is the set of all numbers relatively prime to $n$ that are greater than or equal to one or less than or equal to $n-1$ is an Abelian ...

Q&A for people studying math at any level and professionals in related fields

When can we say a multiplicative group of integers modulo $n$, i.e., $U_n$ is cyclic? $$U_n=\ {a \in\mathbb Z_n \mid \gcd (a,n)=1 \}$$ I searched the internet but did ...

Limit sequence (Un) and (Vn) Ask Question Asked 9 years, 3 months ago Modified 9 years, 3 months ago

I have a confusion regarding how to check whether a wff is satisfiable, unsatisfiable and valid. As far as I understood, valid means the truth table must be a tautology, otherwise it is not a val...

Suppose that $ (x_n)$ and $ (y_n)$ are convergent sequences and let un=min {xn,yn}. Prove that (un) is a convergent sequence Ask Question Asked 11 years, 6 months ago Modified 11 years, 6 months ago

Aug 3, 2023 · (If you know about ring theory.) Since $\mathbb Z_n$ is an abelian group, we can consider its endomorphism ring (where addition is component-wise and multiplication is given by …