Newbetuts

Prove that the topology of a topological space (X, T) is the discrete one if and only if each point of X is open. [duplicate]

Prove that if $x$ is odd then $x^2 -1$ is divisible by $8$.

Proof for Integral Inequality $|\int f| \le \int |f|$ - is it sufficient enough?

Are professional mathematicians concerned with formalizing infinitely many dependent choices?

Counterexamples to proofs of correct statements

Proving the number of $n$ length binary strings with no consecutive $1's$ $b_n$ is equal to $b_{n-1} + b_{n-2}$

Which do you recommend for learning how to write proofs — How to Prove it by Velleman, or How to Solve it by Polya?

Prove that F $ \in \mathbb{R} $ is closed if and only if every Cauchy sequences contained in F has a limit that is also an element of F.

The product of all the elements of a finite abelian group

Critique my proof of: Suppose $A$, $B$, $C$, and $D$ are sets. Prove that $(A \times B) \cup (C \times D) \subseteq (A \cup C) \times (B \cup D)$.

Why does proof by contrapositive make intuitive sense?

Critique my proof of: Suppose $A$ and $B$ are sets. Then $A \times B = B \times A \iff A = \emptyset, B = \emptyset,$ or $A = B$

Define $S\equiv\{ x\in \mathbb{Q}\mid x^2<2\}$. Show that $\sup S=\sqrt{2} $.

Papers with unorthodox writing style

Induction proof for the lengths of well-formed formulas (wffs)

Proofs from the "Ugly Book"

New posts in proof-writing

If $n$ is an odd integer, then there exist integers $a$ and $b$ such that $n=a^2-b^2$. [duplicate]

How to make sure a proof is correct

Proving that the series 1 + ... + $1 / \sqrt{x}$ < $2 \sqrt{x}$

Critique my proof of: $A \times (B \cap C) = (A \times B) \cap (A \times C)$

Prove that the topology of a topological space (X, T) is the discrete one if and only if each point of X is open. [duplicate]

Prove that if $x$ is odd then $x^2 -1$ is divisible by $8$.

Proof for Integral Inequality $|\int f| \le \int |f|$ - is it sufficient enough?

Are professional mathematicians concerned with formalizing infinitely many dependent choices?

Counterexamples to proofs of correct statements

Proving the number of $n$ length binary strings with no consecutive $1's$ $b_n$ is equal to $b_{n-1} + b_{n-2}$

Which do you recommend for learning how to write proofs — How to Prove it by Velleman, or How to Solve it by Polya?

Prove that F $ \in \mathbb{R} $ is closed if and only if every Cauchy sequences contained in F has a limit that is also an element of F.

The product of all the elements of a finite abelian group

Critique my proof of: Suppose $A$, $B$, $C$, and $D$ are sets. Prove that $(A \times B) \cup (C \times D) \subseteq (A \cup C) \times (B \cup D)$.

Why does proof by contrapositive make intuitive sense?

Critique my proof of: Suppose $A$ and $B$ are sets. Then $A \times B = B \times A \iff A = \emptyset, B = \emptyset,$ or $A = B$

Define $S\equiv\{ x\in \mathbb{Q}\mid x^2<2\}$. Show that $\sup S=\sqrt{2} $.

Papers with unorthodox writing style

Induction proof for the lengths of well-formed formulas (wffs)

Proofs from the "Ugly Book"