New posts in proof-explanation

$\{(x,f(x)): x\in E\}$ is compact in $\mathbb R^2 \implies f:E\to\mathbb R$ is continuous

real-analysis analysis solution-verification proof-explanation

Why is $\prod_{k = 1}^t p_k^{\alpha_k - 1}(p_k-1) = n \prod_{p\mid n} \left(1 - \frac {1}{p} \right)$?

group-theory elementary-number-theory finite-groups proof-explanation totient-function

Why isn't mathematical induction a circular argument?

sequences-and-series proof-explanation induction

Understanding proof that continuous image of connected is connected

general-topology proof-explanation connectedness

Question about series rearrangement in Baby Rudin (theorem 3.54).

real-analysis sequences-and-series proof-explanation

A doubt about the construction of a linear map $T$ such that $T:\mathbb R^N \to \mathbb R^p$ such that $K \cap \operatorname{ker} T = \{0\}$

differential-geometry vector-spaces linear-transformations proof-explanation smooth-manifolds

Small question about Gauss's lemma (polynomial)

abstract-algebra polynomials proof-explanation irreducible-polynomials

Proof Strategy - Without Stokes's Theorem - Calculate $\iint_S \operatorname{curl} \mathbf{F} \cdot\; d\mathbf{S}$ for $\mathbf{F} = yz^2\mathbf{i}$

multivariable-calculus proof-explanation

Confusion in GH Hardy's proof of $\lim_{x\to \infty} (f(x)+f'(x))=0\implies \lim_{x\to \infty} f(x)=0 \land \lim_{x\to \infty} f'(x)=0$

real-analysis proof-explanation

For which natural numbers $n$ is $\sqrt n$ irrational? How would you prove your answer? [duplicate]

proof-writing proof-explanation

Why is paracompactness needed to prove a regular space is normal?

general-topology proof-explanation separation-axioms paracompactness

Proof of $x=y \rightarrow [P(x) \rightarrow P(y)]$

logic proof-explanation first-order-logic

If $A$ is an uncountable set and $B \subset A$, $B \neq A$, how can i prove that $B$ is also uncountable?

solution-verification proof-explanation

Show that every local homeomorphism is continuous and open therefore bijective local homeomorphism is a homeomorphism

general-topology functions proof-verification proof-writing proof-explanation

If a finite group $G$ of order $n$ has at most one subgroup of each order $d\mid n$, then $G$ is cyclic

abstract-algebra group-theory finite-groups proof-explanation

Proving every infinite set $S$ contains a denumerable subset

real-analysis elementary-set-theory proof-verification proof-writing proof-explanation

Can the distributive law be proven using only ∧-elimination/introduction and ∨-elimination/introduction?

logic proof-explanation propositional-calculus

Mistake in proof about vector spaces

linear-algebra vector-spaces proof-explanation

A Question on Epsilon-Delta Proofs in Measure Theory

measure-theory proof-explanation lp-spaces alternative-proof epsilon-delta

Conceptual question about the strategy used in the following theorem: Every Ideal of $F[x]$ is Principal

abstract-algebra polynomials ring-theory proof-explanation